TY - JOUR
A1 - Chinnasamy, R.
A1 - Ravi, J.
A1 - Pradeep, V.V.
A1 - Manoharan, D.
A1 - Emmerling, Franziska
A1 - Bhattacharya, Biswajit
A1 - Ghosh, S.
T1 - Adaptable Optical Microwaveguides From Mechanically Flexible Crystalline Materials
N2 - Flexible organic crystals (elastic and plastic) are important materials for optical waveguides, tunable optoelectronic devices, and photonic integrated circuits. Here, we present highly elastic organic crystals of a Schiff base, 1-((E)-(2,5-dichlorophenylimino)methyl)naphthalen-2-ol (1), and an azine molecule, 2,4-dibromo-6-((E)-((E)-(2,6-dichlorobenzylidene)hydrazono)methyl)phenol (2). These microcrystals are highly flexible under external mechanical force, both in the macroscopic and the microscopic regimes. The mechanical flexibility of these crystals arises as a result of weak and dispersive C−H⋅⋅⋅Cl, Cl⋅⋅⋅Cl, Br⋅⋅⋅Br, and π⋅⋅⋅π stacking interactions. Singly and doubly-bent geometries were achieved from their straight shape by a micromechanical approach using the AFM cantilever tip. Crystals of molecules 1 and 2 display a bright-green and red fluorescence (FL), respectively, and selective reabsorption of a part of their FL band. Crystals 1 and 2 exhibit optical-path-dependent low loss emissions at the termini of crystal in their straight and even in extremely bent geometries. Interestingly, the excitation position-dependent optical modes appear in both linear and bent waveguides of crystals 1 and 2, confirming their light-trapping ability.
KW - Crystal growth
KW - Fluorescence
KW - Mechanophotonics
KW - Micromanipulation
KW - Optical waveguides
PY - 2022
U6 - https://doi.org/10.1002/chem.202200905
SN - 0947-6539
SP - 1
EP - 8
PB - Wiley VHC-Verlag
AN - OPUS4-55018
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Belenguer, A.
A1 - Lampronti, G.
A1 - Michalchuk, Adam
A1 - Emmerling, Franziska
A1 - Sanders, J.
T1 - Quantitative reversible one pot interconversion of three crystalline polymorphs by ball mill grinding
N2 - We demonstrate here using a disulfide system the first example of reversible, selective, and quantitative transformation between three crystalline polymorphs by ball mill grinding. This includes the discovery of a previously unknown polymorph. Each polymorph is reproducibly obtained under well-defined neat or liquid-assisted grinding conditions, revealing subtle control over the apparent thermodynamic stability. We discovered that the presence of a contaminant as low as 1.5% mol mol−1 acting as a template is required to enable all these three polymorph transformations. The relative stabilities of the polymorphs are determined by the sizes of the nanocrystals produced under different conditions and by surface interactions with small amounts of added solvent. For the first time, we show evidence that each of the three polymorphs is obtained with a unique and reproducible crystalline size. This mechanochemical approach gives access to bulk quantities of metastable polymorphs that are inaccessible through recrystallisation.
KW - Mechanochemistry
KW - Polymorph
KW - XRD
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-549934
SP - 1
EP - 7
PB - Royal Society of Chemistry
AN - OPUS4-54993
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - George, Janine
A1 - Petretto, G.
A1 - Naik, Aakash Ashok
A1 - Esters, M.
A1 - Jackson, A. J.
A1 - Nelson, R.
A1 - Dronskowski, R.
A1 - Rignanese, G.-M.
A1 - Hautier, G.
T1 - Automated bonding analysis with crystal orbital Hamilton populuations
N2 - Automated bonding analysis software has been developed based on Crystal Orbital Hamilton Populations to facilitate high-throughput bonding analysis and machine-learning of bonding features. This work presents the software and discusses its applications to simple and complex materials such as GaN, NaCl, the oxynitrides XTaO2N (X=Ca, Ba, Sr) and Yb14Mn1Sb11.
KW - Chemical bonds
KW - Automation
KW - High-throughput
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-551641
SN - 2192-6506
SP - 1
EP - 11
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-55164
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - George, Janine
T1 - DFT-based Phonon-computations for "Considering the Role of Ion Transport in Diffuson-Dominated Thermal Conductivity"
N2 - These are the harmonic phonon and Grüneisen parameter computations for the publication "Considering the Role of Ion Transport in Diffuson-Dominated Thermal Conductivity" (https://doi.org/10.1002/aenm.202200717). VASP and Phonopy outputs are included in this data set.
KW - Thermal conductivity
KW - Phonons
PY - 2021
U6 - https://doi.org/10.5281/zenodo.5116360
PB - Zenodo
CY - Geneva
AN - OPUS4-55168
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - George, Janine
A1 - Petretto, G.
A1 - Naik, Aakash Ashok
A1 - Esters, M.
A1 - Jackson, A. J.
A1 - Nelson, R.
A1 - Dronskowski, R.
A1 - Rignanese, G.-M.
A1 - Hautier, G.
T1 - Automated bonding analysis with crystal orbital Hamilton populations (program code LobsterPy)
N2 - This is the code for the program LobsterPy that can be used to automatically analyze and plot outputs of the program Lobster.
KW - Automation
KW - High-throughput computations
KW - Bonding analysis
PY - 2022
UR - https://doi.org/10.5281/zenodo.6320074
UR - https://doi.org/10.5281/zenodo.6415169
UR - https://doi.org/10.5281/zenodo.6415336
UR - https://doi.org/10.5281/zenodo.6581118
U6 - https://doi.org/10.5281/zenodo.6320073
PB - Zenodo
CY - Geneva
AN - OPUS4-55174
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - George, Janine
T1 - Raw data for "Automated bonding analysis with crystal orbital Hamilton populations"
N2 - Raw data corresponding to the following paper: 10.1002/cplu.202200123.
KW - Automation
KW - High-throughput computations
KW - Bonding analysis
PY - 2022
UR - https://doi.org/10.5281/zenodo.6373369
U6 - https://doi.org/10.5281/zenodo.6373368
PB - Zenodo
CY - Geneva
AN - OPUS4-55175
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - George, Janine
A1 - Naik, Aakash Ashok
A1 - Jackson, A. J.
A1 - Baird, S.
T1 - Scripts to reproduce "Automated bonding analysis with crystal orbital Hamilton populations"
N2 - This repo allows to recreate our publication: https://doi.org/10.1002/cplu.202200123 In contrast to 0.2.2, we fixed an issue with absolute path.
KW - Automation
KW - High-throughput computations
KW - Bonding analysis
PY - 2022
UR - https://github.com/JaGeo/LobsterAutomation
UR - https://doi.org/10.5281/zenodo.6421928
UR - https://doi.org/10.5281/zenodo.6595062
UR - https://doi.org/10.5281/zenodo.6599556
UR - https://doi.org/10.5281/zenodo.6674670
UR - https://doi.org/10.5281/zenodo.6704163
U6 - https://doi.org/10.5281/zenodo.6421927
PB - Zenodo
CY - Geneva
AN - OPUS4-55177
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Accorsi, M.
A1 - Tiemann, M.
A1 - Wehrhan, L.
A1 - Finn, Lauren M.
A1 - Cruz, R.
A1 - Rautenberg, Max
A1 - Emmerling, Franziska
A1 - Heberle, J.
A1 - Keller, B. G.
A1 - Rademann, J.
T1 - Pentafluorophosphato-Phenylalanines: Amphiphilic Phosphotyrosine Mimetics Displaying Fluorine-Specific Protein Interactions
N2 - Phosphotyrosine residues are essential functional switches in health and disease. Thus, phosphotyrosine biomimetics are crucial for the development of chemical tools and drug molecules. We report here the discovery and investigation of pentafluorophosphato amino acids as novel phosphotyrosine biomimetics. A mild acidic pentafluorination protocol was developed and two PF5-amino acids were prepared and employed in peptide synthesis. Their structures, reactivities, and fluorine-specific interactions were studied by NMR and IR spectroscopy, X-ray diffraction, and in bioactivity assays. The mono-anionic PF5 motif displayed an amphiphilic character binding to hydrophobic surfaces, to water molecules, and to protein-binding sites, exploiting charge and H−F-bonding interactions. The novel motifs bind 25- to 30-fold stronger to the phosphotyrosine binding site of the protein tyrosine phosphatase PTP1B than the best current biomimetics, as rationalized by computational methods, including molecular dynamics simulations.
KW - Chemical Biology
KW - Drug Development
KW - Pentafluorophosphates
KW - Phosphotyrosine Biomimetics
KW - Protein Tyrosine Phosphatases
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-549984
SN - 1433-7851
VL - 134
IS - 25
SP - 1
EP - 6
PB - Wiley-VCH GmbH
AN - OPUS4-54998
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Data-driven chemical understanding
N2 - Chemical heuristics are essential to understanding molecules and materials in chemistry. The periodic table, atomic radii, and electronegativities are only a few examples. Initially, they have been developed by a combination of physical insight and a limited amount of data. It is now possible to test these heuristics and generate new ones using automation based on Materials Informatic tools like pymatgen and greater amounts of data from databases such as a Materials Project. In this session, I'll speak about heuristics and design rules based on coordination environments and the concept of chemical bonding. For example, we have tested the Pauling rules which describe the stability of materials based on coordination environments and their connections on 5000 oxides from the Materials Project. In addition, we have created automated processes for analyzing the chemical bonding situation in crystalline materials with Lobster (www.cohp.de) in order to discover new heuristics and design rules.
T2 - Materials Project Seminar Series
CY - Online meeting
DA - 18.05.2022
KW - DFT
KW - Chemical heuristics
KW - Crystal Orbital Hamilton Populations
KW - Machine learning
KW - Phonons
PY - 2022
UR - https://www.youtube.com/watch?v=e7zYrz6fgog
UR - https://next-gen.materialsproject.org/community/seminar
AN - OPUS4-55008
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Loges, A.
A1 - Scholz, G.
A1 - Amadeu de Sosa, Nader
A1 - Jingjing, S.
A1 - Emmerling, Franziska
A1 - John, T.
A1 - Paulus, B.
A1 - Braun, T.
T1 - Studies on the local structure of the F/OH site in topaz by magic angle spinning nuclear magnetic resonance and Raman spectroscopy
N2 - he mutual influence of F and OH groups in neighboring sites in topaz (Al2SiO4(F,OH)2) was investigated using magic angle spinning nuclear magnetic resonance (MAS NMR) and Raman spectroscopy. The splitting of 19F and 1H NMR signals, as well as the OH Raman band, provides evidence for hydrogen bond formation within the crystal structure. Depending on whether a given OH group has another OH group or fluoride as its neighbor, two different hydrogen bond constellations may form: either OH···O···HO or F···H···O. The proton accepting oxygen was determined to be part of the SiO4 tetrahedron using 29Si MAS NMR. Comparison of the MAS NMR data between an OH-bearing and an OH-free topaz sample confirms that the 19F signal at −130 ppm stems from F− ions that take part in H···F bonds with a distance of ∼ 2.4 Å, whereas the main signal at −135 ppm belongs to fluoride ions with no immediate OH group neighbors. The Raman OH sub-band at 3644 cm−1 stems from OH groups neighboring other OH groups, whereas the sub-band at 3650 cm−1 stems from OH groups with fluoride neighbors, which are affected by H···F bridging. The integrated intensities of these two sub-bands do not conform to the expected ratios based on probabilistic calculations from the total OH concentration. This can be explained by a difference in the polarizability of the OH bond between the different hydrogen bond constellations or partial order or unmixing of F and OH, or a combination of both. This has implications for the quantitative interpretation of Raman data on OH bonds in general and their potential use as a probe for structural (dis-)order. No indication of tetrahedrally coordinated Al was found with 27Al MAS NMR, suggesting that the investigated samples likely have nearly ideal Al/Si ratios, making them potentially useful as high-density electron microprobe reference materials for Al and Si, as well as for F.
KW - Topas
KW - NMR
KW - XRD
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-561863
SN - 1617-4011
VL - 34
IS - 5
SP - 507
EP - 521
PB - Copernicus Publications
CY - Göttingen
AN - OPUS4-56186
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Emmerling, Franziska
A1 - Hoch, C.
T1 - Laudatio Prof. Dr.-Ing. Caroline Röhr
N2 - It is a laudatio on the ocations of Prof. Dr.-Ing. Caroline Röhrs 60th birthday.
KW - Metal-oxides
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-561877
SN - 0044-2313
VL - 648
IS - 10
SP - 1
EP - 2
PB - John Wiley & Sons, Ltd
AN - OPUS4-56187
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Mit Hilfe künstlicher Intelligenz neue Materialien finden
N2 - In diesem Vortrag für Schüler*innen, die an der nationalen Auswahl der internationalen Chemieolympiade teilnehmen, stellte ich meinen akademischen Werdegang und das Fach Materialinformatik und die Forschung in diesem Bereich vor.
T2 - Landesseminar zur Internationalen Chemieolympiade in Berlin-Brandenburg
CY - Berlin, Germany
DA - 30.10.2022
KW - Materialinformatik
KW - Automatisierung
KW - Computerchemie
PY - 2022
AN - OPUS4-56128
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Naik, Aakash Ashok
A1 - George, Janine
T1 - New descriptors for materials properties based on bonding indicators
N2 - Includes a summary of the Ph.D. project that deals with generating a database populated with materials bonding properties and how we intend to gain deeper insights into material properties through this research.
T2 - SALSA 2022
CY - Berlin, Germany
DA - 15.09.2022
KW - Bonding analysis
KW - Automation
KW - Materials Informatics
KW - Computational Chemistry
PY - 2022
AN - OPUS4-56142
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Data-driven chemical understanding with geometrical and quantum-chemical bonding analysis
N2 - Chemical bonding and coordination environments are crucial descriptors of material properties. They have previously been applied to creating chemical design guidelines and chemical heuristics. They are currently being used as features in machine learning more and more frequently. I will discuss implementations and algorithms (ChemEnv and LobsterEnv) for identifying these coordination environments based on geometrical characteristics and chemical bond quantum chemical analysis. I'll demonstrate how these techniques helped in testing chemical heuristics like the Pauling rule and thereby improved our understanding of chemistry. I'll also show how these tools can be used to create new design guidelines and a new understanding of chemistry. To use quantum-chemical bonding analysis on a large-scale and for machine-learning approaches, fully automatic workflows and analysis tools have been developed. After presenting the capabilities of these tools, I will also point out how these developments relate to the general trend towards automation in the field of density functional based materials science.
T2 - ICAMS Interdisciplinary Centre for Advanced Materials Simulation Seminar Series
CY - Online meeting
DA - 24.11.2022
KW - Automation
KW - High-throughput
KW - Machine learning
KW - Materials informatics
KW - Bonding Analysis
PY - 2022
AN - OPUS4-56417
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Automation and workflows incomputational materials science
N2 - This talk introduced the audience to automation and workflows in the field of computational materials science. The audience were the members of the FONDA Sonderforschungsbereich at HU Berlin
T2 - FONDA Seminar Series
CY - Berlin, Germany
DA - 10.10.2022
KW - Automation
KW - Workflows
KW - Materials Informatics
PY - 2022
AN - OPUS4-56419
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Karafiludis, Stephanos
A1 - Kochovski, Z.
A1 - Scoppola, E.
A1 - Emmerling, Franziska
A1 - Stawski, Tomasz
T1 - Crystallization study of transition metal phosphates: a new example for non-classical crystallization theory
N2 - Industrial and agricultural waste streams (waste waters, sludges, tailings etc.), which contain high concentrations of NH4+, PO43- and transition metals, are environmentally harmful due to their toxic pollutants. At the same time, phosphorus and selective transition metals such as Cobalt could be potentially depleted as a critical raw material due to the high demand and rapidly declining natural ore deposits. Therefore, due to simultaneous scarcity and abundance, the phosphorus and 3d metal recovery from agricultural, industrial, mining, or urban wastewaters have been an important factor in sustaining our global consumption and preservation of the natural environment. Typically, separate pathways have been considered to extract hazardous substances such as transition metals or phosphate, independently from each other. Here, we report the synthesis routes for transition metal phosphate (TMP) compounds (M3(PO4)2∙8H2O, NH4MPO4∙6H2O, M = Ni2+, Co2+, NixCo1-x2+ M-struvite and M-phosphate octahydrate), which allow for P, ammonia and metal co-precipitation. The precipitation of these compounds from industrial and agricultural waste waters could be a promising P-recovery route. Through adjusting the reaction conditions, the stability, crystallite size and morphology of the as-obtained TMP could be controlled. Detailed investigations of the precipitation process using ex- and in-situ techniques provided new insights into their non-classical crystallization mechanism/crystal engineering of these materials. These TMPs involve transitional colloidal nanophases which subsequently aggregate and condense to final crystals after extended reaction times. However, the reaction kinetics of the formation of a final crystalline product vary significantly depending on the metal cation involved in the precipitation process. Ni-struvite is stable in a wide reactant concentration range and at different metal/phosphorus (M/P)-ratios, whereas Co tends to form Co-struvite and/or Co-phosphate octahydrate depending on the (M/P)-ratio. The mixed NixCo1-x system shows a significantly different crystallization behavior and reaction kinetics of the precipitation compared to the pure endmembers. The observed various degree of stability could be linked to the octahedral metal coordination environment in these compounds. The achieved level of control over the precipitates, is highly desirable for 3d- and P-recovery methods. Under this paradigm, the crystals can be potentially upcycled as precursor materials for (electro)catalytical applications.
T2 - Adlershofer Forschungsforum 2022
CY - Berlin, Gemany
DA - 11.11.2022
KW - Transition metal
KW - Phosphates
KW - Non-classical crystallization
KW - In-situ SAXS/WAXS
KW - Cryo-TEM
PY - 2022
AN - OPUS4-56479
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Zänker, Steffen
A1 - Scholz, G.
A1 - Marquardt, Julien
A1 - Emmerling, Franziska
T1 - Structural changes in Ba-compounds of different hardness induced by high-energy ball milling – evidenced by 137Ba NMR and X-ray powder diffraction
N2 - Changes in the global bulk and local structures, of three different barium compounds (BaZrO3, BaF2, and BaFCl),were induced by mechanical milling and followed using X-ray powder diffraction (PXRD), subsequent microstructure analysis, and 137Ba solid state NMR spectroscopy. Harder materials like BaZrO3 experience significantly higher structural changes upon milling than softer materials like BaF2. Moreover, soft materials with layered structures, like BaFCl, show a pronounced structural change during the milling process. By combining PXRD and solid state NMR, detailed information on the changes to the global and local structures were obtained, which are of interest for mechanochemical synthesis, mechanically treated catalysts or ionic conductors.
KW - Mechanochemistry
KW - X-ray diffraction
KW - Solid state NMR
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-547397
SN - 0044-2313
VL - 648
IS - 10
SP - 1
EP - 8
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-54739
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bernges, T.
A1 - Hanus, R.
A1 - Wankmiller, B.
A1 - Imasato, K.
A1 - Lin, S.
A1 - Ghidiu, M.
A1 - Gerlitz, M.
A1 - Peterlechner, M.
A1 - Graham, S.
A1 - Hautier, G.
A1 - Pei, Y.
A1 - Hansen, M. R.
A1 - Wilde, G.
A1 - Snyder, G. J.
A1 - George, Janine
A1 - Agne, M T.
A1 - Zeier, W. G.
T1 - Considering the Role of Ion Transport in Diffuson-Dominated Thermal Conductivity
N2 - Next-generation thermal management requires the development of low lattice thermal conductivity materials, as observed in ionic conductors. For example, thermoelectric efficiency is increased when thermal conductivity is decreased. Detrimentally, high ionic conductivity leads to thermoelectric device degradation. Battery safety and design also require an understanding of thermal transport in ionic conductors. Ion mobility, structural complexity, and anharmonicity have been used to explain the thermal transport properties of ionic conductors. However, thermal and ionic transport are rarely discussed in direct comparison. Herein, the ionic conductivity of Ag+ argyrodites is found to change by orders of magnitude without altering the thermal conductivity. Thermal conductivity measurements and two-channel lattice dynamics modeling reveal that the majority of Ag+ vibrations have a non-propagating diffuson-like character, similar to amorphous materials. It is found that high ionic mobility is not a requirement for diffuson-mediated transport. Instead, the same bonding and structural traits that can lead to fast ionic conduction also lead to diffuson-mediated transport. Bridging the fields of solid-state ionics and thermal transport, it is proposed that a vibrational perspective can lead to new design strategies for functional ionic conducting materials. As a first step, the authors relate the so-called Meyer-Neldel behavior in ionic conductors to phonon occupations.
KW - Diffusons
KW - DFT
KW - Phonons
KW - Thermoelectrics
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-547140
SN - 1614-6832
VL - 12
IS - 22
SP - 1
EP - 13
PB - Wiley VHC-Verlag
AN - OPUS4-54714
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Michalchuk, Adam
A1 - Morrison, C.
T1 - From lattice vibrations to molecular dissociation
N2 - The ease with which an energetic material can be initiated by mechanical impact is a critical parameter directing material safety and application. While impact sensitivity metrics are traditionally derived experimentally, recent developments have highlighted that the phenomenon is amenable to first principles simulation. In this chapter, we will outline a fully ab initio approach to predict the relative impact sensitivities of energetic materials based on the mechanochemical principles that link the impact event to vibrational energy transfer.
This mechanism is key to rationalizing how a mechanical impact—which deposits energy into the low-frequency lattice vibrations—results in a molecular response. By simulating the vibrational energy levels (the so-called phonon density of states, PDOS) using first-principles computational methods (typically dispersion-corrected plane-wave density functional theory, PW-DFT) we can calculate the relative rate of energy propagation from the delocalized low-energy lattice vibrations through to the localized molecular modes. The latter traps the energy, which eventually results in bond rupture through heightened vibrational excitation.
This method, based on vibrational up-pumping, offers a route toward predicting the impact sensitivities of a broad range of energetic materials, provided the crystal structure of the compound (or salt or co-crystal) is known. While it does not offer insight into the sensitizing roles undoubtedly played by crystal defects or grain boundaries, it does provide a level of understanding at the molecular and crystal packing levels. Correspondingly, this approach offers a feedback mechanism to chemists and materials scientists to guide the design of new materials with desired impact sensitivity behavior.
KW - Energetic materials
KW - Density functional theory
KW - Material design
PY - 2022
U6 - https://doi.org/10.1016/B978-0-12-822971-2.00010-3
VL - 22
SP - 215
EP - 232
PB - Elsevier B.V.
AN - OPUS4-54717
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Aree, T.
A1 - McMonagle, C. J.
A1 - Michalchuk, Adam
A1 - Chernyshov, D.
T1 - Low-frequency lattice vibrations from atomic displacement parameters of a-FOX-7, a high energy density material
N2 - Highly anharmonic thermal vibrations may serve as a source of structural instabilities resulting in phase transitions, chemical reactions and even the mechanical disintegration of a material. Ab initio calculations model thermal motion within a harmonic or sometimes quasi-harmonic approximation and must be complimented by experimental data on temperature-dependent vibrational frequencies. Here multi-temperature atomic displacement parameters (ADPs), derived from a single-crystal synchrotron diffraction experiment, are used to characterize low-frequency lattice vibrations in the alpha-FOX-7 layered structure. It is shown that despite the limited quality of the data, the extracted frequencies are reasonably close to those derived from inelastic scattering, Raman measurements and density functional theory (DFT) calculations. Vibrational anharmonicity is parameterized by the Grüneisen parameters, which are found to be very different for in-layer and out-of-layer vibrations.
KW - Energetic Materials
KW - DFT
KW - Structural dynamics
KW - X-ray diffraction
PY - 2022
U6 - https://doi.org/10.1107/S2052520622002700
SN - 2052-5206
VL - 78
SP - 376
EP - 384
PB - Wiley-Blackwell
CY - Oxford
AN - OPUS4-54832
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mazzeo, P. P.
A1 - Prencipe, M.
A1 - Feiler, Torvid
A1 - Emmerling, Franziska
A1 - Bacchi, A.
T1 - On the mechanism of cocrystal mechanochemical reaction via low melting eutectic: A time-resolved in situ monitoring investigation
N2 - Mechanochemistry has become a sustainable and attractive cost-effective synthetic technique, largely used within the frame of crystal engineering. Cocrystals, namely, crystalline compounds made of different chemical entities within the same crystal structure, are typically synthesized in bulk via mechanochemistry; however, whereas the macroscopic aspects of grinding are becoming clear, the fundamental principles that underlie mechanochemical cocrystallization at the microscopic level remain poorly understood. Time-resolved in situ (TRIS) monitoring approaches have opened the door to exceptional detail regarding mechanochemical reactions. We here report a clear example of cocrystallization between two solid coformers that proceeds through the formation of a metastable low melting binary eutectic phase. The overall cocrystallization process has been monitored by time-resolved in situ (TRIS) synchrotron X-ray powder diffraction with a customized ball milling setup, currently available at μ Spot beamline at BESSY-II, Helmholtz-Zentrum Berlin. The binary system and the low melting eutectic phase were further characterized via DSC, HSM, and VT-XRPD.
KW - Mechanochemistry
KW - In situ
KW - Cocrystal
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-552977
SN - 1528-7505
VL - 22
IS - 7
SP - 4260
EP - 4267
PB - ACS Publ.
CY - Washington, DC
AN - OPUS4-55297
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Lakshmipathi, M.
A1 - Dey, S.
A1 - Emmerling, Franziska
A1 - Bhattacharya, Biswajit
A1 - Michalchuk, Adam
T1 - Designing Dual Mechanical Response in Molecular Crystals through Cocrystallization
N2 - Two isomorphous crystals are reported based on a naphthylvinylpyridine coformer. The crystals are mechanically flexible and exhibit photosalient response to UV irradiation. We therefore show how multiple mechanical phenomena can be simultaneously designed into a single material by cocrystallization.
KW - Cocrystal
KW - Mechanical response
PY - 2022
U6 - https://doi.org/10.1021/acs.cgd.2c00913
SN - 1528-7483
VL - 22
SP - 6838
EP - 6843
PB - ACS Publ.
CY - Washington, DC
AN - OPUS4-56561
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Sergievskaya, A.
A1 - Absil, R.
A1 - Chauvin, A.
A1 - Yusenko, Kirill
A1 - Vesely, J.
A1 - Godfroid, T.
A1 - Konsstantinidis, S.
T1 - Sputtering onto liquids: How does the liquid viscosity affect the formation of nanoparticles and metal films?
N2 - This paper reports on the effect of the solvent viscosity on the formation of gold nanoparticles (Au NPs) during Sputtering onto Liquid (SoL) process. All other parameters related to the plasma and the host liquid are kept constant. SoL is a simple highly reproducible approach for preparation of colloidal dispersions of small naked NPs. The properties of the final product are determined by both the sputtering parameters and the host liquid characteristics. As a model system we chose to sputter a gold target by a direct-current magnetron discharge onto a line of polymerized rapeseed oils having similar surface tension (32.6 ― 33.1 mJ·m-2 at RT). It was found that well dispersed Au NPs grow in the bulk solution of oils with low viscosities (below 630 cP at 25 °C) while gold films form onto the surface of high viscosity liquids (more than 1000 cP at 25 °C). The mean diameter of the individual Au NPs slightly increases with oil viscosity and is in range about 2.1―2.5 nm according to transmission electron microscopy.
KW - Liquid spattering
KW - Nanoparticles
PY - 2023
U6 - https://doi.org/10.1039/D2CP03038A
SN - 1463-9084
VL - 25
IS - 4
SP - 2803
EP - 2809
PB - RSC Publ.
CY - Cambridge
AN - OPUS4-56562
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Automation and Workflows in Computational Materials Science
N2 - This talks describes why we need automation and workflows in materials informatics. It introduces tools to automatize tasks in computational materials science. Furthermore, a bonding analysis and a phonon workflow are presented.
T2 - Seminar in Theoretical Chemistry Group atFU Berlin
CY - Berlin, Germany
DA - 06.12.2022
KW - Automation
KW - Workflows
KW - Density functional theory
PY - 2022
AN - OPUS4-56524
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Linberg, Kevin
A1 - Emmerling, Franziska
A1 - Michalchuk, Adam
T1 - Unintended Rate Enhancement in Mechanochemical Kinetics by Using Poly(methyl methacrylate) Jars
N2 - Time-resolved in situ (TRIS) X-ray diffraction has changed how mechanochemical transformations are studied but requires the use of X-ray transparent jars often made from poly(methyl methacrylate) (PMMA). However, using PMMA jars can alter the apparent kinetics of mechanochemical polymorphism by an order of magnitude, questioning the interpretability of established TRIS methods. Our results suggest that rate enhancement in PMMA jars may not be dominated by chemical effects of the polymer, but rather a result of different equilibrium temperatures within the jar. These features must be better understood before control over mechanochemical reactions can be achieved.
KW - Mechanochemistry
KW - Organic compounds
KW - Polymers
KW - Materials
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-565276
SN - 1528-7483
SP - 1
EP - 5
PB - ACS Publications
AN - OPUS4-56527
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ravi, J.
A1 - Feiler, Torvid
A1 - Mondal, A.
A1 - Michalchuk, Adam
A1 - Reddy, C. M.
A1 - Bhattacharya, Biswajit
A1 - Emmerling, Franziska
A1 - Chandrasekar, R.
T1 - Plastically bendable organic crystals for monolithic and hybrid micro-optical circuits
N2 - Fluorescent plastically bendable crystals are a promising alternative to silicon-based materials for fabricating photonic integrated circuits, owing to their optical attributes and mechanical compliance. Mechanically bendable plastic organic crystals are rare. Their formation requires anisotropic intermolecular interactions and slip planes in the crystal lattice. This work presents three fluorescent plastically bendable crystalline materials namely, 2-((E)-(6-methylpyridin-2-ylimino)methyl)-4-chlorophenol (SB1), 2-((E)-(6-methylpyridin-2-ylimino)methyl)-4-bromophenol (SB2), and 2-((E)-(6-Bromopyridin-2-ylimino)methyl)-4-bromophenol (SB3) molecules. The crystal plasticity in response to mechanical stress facilitates the fabrication of various monolithic and hybrid (with a tip-to-tip coupling) photonic circuits using mechanical micromanipulation with an atomic force microscope cantilever tip. These plastically bendable crystals act as active (self-guiding of fluorescence) and passive waveguides both in straight and extremely bent (U-, J-, and O-shaped) geometries. These microcircuits use active and passive waveguiding principles and reabsorbance and energy-transfer mechanisms for their operation, allowing input-selective and direction-specific signal transduction.
KW - Flexible crystals
KW - Flexible waveguide
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-565302
SN - 2195-1071
SP - 1
EP - 10
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-56530
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Feiler, Torvid
A1 - Bhattacharya, Biswajit
A1 - Michalchuk, Adam
A1 - Rhim, S.-Y.
A1 - Schröder, V.
A1 - List-Kratochvil, E.
A1 - Emmerling, Franziska
T1 - Mechanically plastic molecular crystals for shapeable optic waveguides
N2 - Molecular crystalline materials are usually brittle and are prone to breaking when mechanically stressed. This fragility greatly limits they application in next the generation of adaptable, functional materials. The recent discovery of mechanical compliancy in molecular crystals has solved this problem.1 Based on the nature of the deformation, molecular crystals can be divided into being plastically (irreversibly) or elastically (reversibly) bendable. The plastic deformation is generally associated with anisotropic molecular arrangements and the existence of low energy slip planes which allow a permanent motion within the lattice. Here we report 4-bromo-6-[(6-chloropyridin-2-ylimino)methyl]phenol (CPMBP) as a promising candidate for future waveguide technologies.2 CPMBP has been found to have two different polymorphs with distinct optical and mechanical properties. The brittle crystals of Form I exhibits very weak emission at 605 nm (λex = 425 nm; photoluminescence quantum yield Φ = 0.4 %). In contrast, Form II has a large plastic regime together with a bright emission at 585 nm (λex = 425 nm; Φ = 8.7 %). Taking advantage of the favorable mechanical flexibility and optical properties, Form II was used as a shapeable optical waveguide. By changing the wavelength of the light source, active or passive waveguiding can be realized. CPMBP could thus be used as a flexible wavelength filter.
T2 - 30. Jahrestagung der Deutschen Gesellschaft für Kristallographie
CY - Online meeting
DA - 14.3.2022
KW - Flexible crystals
KW - Polymorphism
KW - Waveguide
PY - 2022
AN - OPUS4-54514
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Feiler, Torvid
A1 - Bhattacharya, Biswajit
A1 - Michalchuk, Adam
A1 - Rhim, S.-Y.
A1 - Schröder, V.
A1 - List-Kratochvil, E.
A1 - Emmerling, Franziska
T1 - Mechanically plastic molecular crystals for shapeable optic waveguides
N2 - Molecular crystalline materials are usually brittle and are prone to breaking when mechanically stressed. This fragility greatly limits they application in next the generation of adaptable, functional materials. The recent discovery of mechanical compliancy in molecular crystals has solved this problem.1 Based on the nature of the deformation, molecular crystals can be divided into being plastically (irreversibly) or elastically (reversibly) bendable. The plastic deformation is generally associated with anisotropic molecular arrangements and the existence of low energy slip planes which allow a permanent motion within the lattice. Here we report 4-bromo-6-[(6-chloropyridin-2-ylimino)methyl]phenol (CPMBP) as a promising candidate for future waveguide technologies.2 CPMBP has been found to have two different polymorphs with distinct optical and mechanical properties. The brittle crystals of Form I exhibits very weak emission at 605 nm (λex = 425 nm; photoluminescence quantum yield Φ = 0.4 %). In contrast, Form II has a large plastic regime together with a bright emission at 585 nm (λex = 425 nm; Φ = 8.7 %). Taking advantage of the favorable mechanical flexibility and optical properties, Form II was used as a shapeable optical waveguide. By changing the wavelength of the light source, active or passive waveguiding can be realized. CPMBP could thus be used as a flexible wavelength filter.
T2 - 30. Jahrestagung der Deutschen Gesellschaft für Kristallographie
CY - Online meeting
DA - 14.3.2022
KW - Flexible crystals
KW - Polymorphism
KW - Waveguide
PY - 2022
AN - OPUS4-54515
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kosareva, E.
A1 - Gainutdinov, R.
A1 - Michalchuk, Adam
A1 - Ananyev, I.
A1 - Muravyev, N.
T1 - Mechanical Stimulation of Energetic Materials at the Nanoscale
N2 - The initiation of energetic materials by mechanical stimuli is a critical stage of their functioning, but remains poorly understood. Using atomic force microscopy (AFM) we explore the microscopic initiation behavior of four prototypical energetic materials: 3,4-dinitropyrazole, 𝜖-CL-20, 𝛼-PETN and picric acid. Along with the various chemical structures, these energetic compounds cover a range of application types: a promising melt-cast explosive, the most powerful energetic compound in use, a widespread primary explosive, and a well-established nitroaromatic explosive from the early development of energetics. For the softest materials (picric acid and 3,4-dinitropyrazole), the surfaces were found to behave dynamically, quickly rearranging in response to mechanical deformation. The pit created by nanoscale friction stimulation on the surface of 3,4-dinitropyrazole doubled in volume upon aging for half an hour. Over the same time frame, a similar pit on picric acid surface increased in volume by more than seven-fold. Remarkably, increased humidity was found to reduce the rate of surface rearrangement, potentially offering an origin for the desensitization of energetic materials when wetted. Finally, we identify an inverse correlation between the surface dynamics and mechanical sensitivity of our test energetic compounds. This strongly suggests that surface dynamics influence a material’s ability to dissipate excess energy, acting as a buffer towards mechanical initiation.
KW - Energetic materials
KW - Mechanical Properties
KW - Mechanical Sensitivity
PY - 2022
U6 - https://doi.org/10.1039/D2CP00832G
VL - 24
IS - 15
SP - 8890
EP - 8900
PB - Royal Society of Chemistry
AN - OPUS4-54562
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Getenet, M.
A1 - Garcia-Ruiz, J. M.
A1 - Otálora, F.
A1 - Emmerling, Franziska
A1 - Al-Sabbagh, Dominik
A1 - Verdugo-Escamilla, E.
T1 - A comprehensive methodology for monitoring evaporitic mineral precipitation and hydrochemical evolution of saline lakes: The case of Lake Magadi soda brine (East African Rift Valley, Kenya)
N2 - Lake Magadi, East African Rift Valley, is a hyperalkaline and saline soda lake highly enriched in Na+, K+, CO32–, Cl–, HCO3–, and SiO2 and depleted in Ca2+ and Mg2+, where thick evaporite deposits and siliceous sediments have been forming for 100 000 years. The hydrogeochemistry and the evaporite deposits of soda lakes are subjects of growing interest in paleoclimatology, astrobiology, and planetary sciences. In Lake Magadi, different hydrates of sodium carbonate/bicarbonate and other saline minerals precipitate. The precipitation sequence of these minerals is a key for understanding the hydrochemical evolution, the paleoenvironmental conditions of ancient evaporite deposits, and industrial crystallization. However, accurate determination of the precipitation sequence of these minerals was challenging due to the dependency of the different hydrates on temperature, water activity, pH and pCO2, which could induce phase transformation and secondary mineral precipitation during sample handling. Here, we report a comprehensive methodology applied for monitoring the evaporitic mineral precipitation and hydrochemical evolution of Lake Magadi. Evaporation and mineral precipitations were monitored by using in situ video microscopy and synchrotron X-ray diffraction of acoustically levitated droplets. The mineral patterns were characterized by ex situ Raman spectroscopy, X-ray diffraction, and scanning electron microscopy. Experiments were coupled with thermodynamic models to understand the evaporation and precipitation-driven hydrochemical evolution of brines. Our results closely reproduced the mineral assemblages, patterns, and textural relations observed in the natural setting. Alkaline earth carbonates and fluorite were predicted to precipitate first followed by siliceous sediments. Among the salts, dendritic and acicular trona precipitate first via fractional crystallization─reminiscent of grasslike trona layers of Lake Magadi. Halite/villiaumite, thermonatrite, and sylvite precipitate sequentially after trona from residual brines depleted in HCO3–. The precipitation of these minerals between trona crystals resembles the precipitation process observed in the interstitial brines of the trona layers. Thermonatrite precipitation began after trona equilibrated with the residual brines due to the absence of excess CO2 input. We have shown that evaporation and mineral precipitation are the major drivers for the formation of hyperalkaline, saline, and SiO2-rich brines. The discrepancy between predicted and actual sulfate and phosphate ion concentrations implies the biological cycling of these ions. The combination of different in situ and ex situ methods and modeling is key to understanding the mineral phases, precipitation sequences, and textural relations of modern and ancient evaporite deposits. The synergy of these methods could be applicable in industrial crystallization and natural brines to reconstruct the hydrogeochemical and hydroclimatic conditions of soda lakes, evaporite settings, and potentially soda oceans of early Earth and extraterrestrial planets.
KW - Crystallization
KW - Precipitation
KW - Crystals
KW - Evaporation
KW - Minerals
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-546712
SN - 1528-7483
VL - 22
IS - 4
SP - 2307
EP - 2317
PB - ACS Publications
CY - Washington, DC
AN - OPUS4-54671
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Martins, Ines
A1 - Al-Sabbagh, Dominik
A1 - Bentrup, U.
A1 - Marquardt, Julien
A1 - Schmid, Thomas
A1 - Scoppola, E.
A1 - Kraus, Werner
A1 - Stawski, Tomasz
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Yusenko, Kirill
A1 - Weidner, Steffen
A1 - Emmerling, Franziska
T1 - Formation Mechanism of a Nano-Ring of Bismuth Cations and Mono-Lacunary Keggin-Type Phosphomolybdate
N2 - A new hetero-bimetallic polyoxometalate (POM) nano-ring was synthesized in a one-pot procedure. The structure consists of tetrameric units containing four bismuth-substituted monolacunary Keggin anions including distorted [BiO8] cubes. The nano-ring is formed via self-assembly from metal precursors in aqueous acidic medium. The compound (NH4)16[(BiPMo11O39)4] ⋅ 22 H2O; (P4Bi4Mo44) was characterized by single-crystal X-ray diffraction, extended X-ray absorption fine structure spectroscopy (EXAFS), Raman spectroscopy, matrix-assisted laser desorption/ionisation-time of flight mass spectrometry (MALDI-TOF), and thermogravimetry/differential scanning calorimetry mass spectrometry (TG-DSC-MS). The formation of the nano-ring in solution was studied by time-resolved in situ small- and wide-angle X-ray scattering (SAXS/WAXS) and in situ EXAFS measurements at the Mo−K and the Bi−L3 edge indicating a two-step process consisting of condensation of Mo-anions and formation of Bi−Mo-units followed by a rapid self-assembly to yield the final tetrameric ring structure.
KW - Bismuth
KW - In situ EXAFS
KW - In situ SAXS/WAXS
KW - Lacunary Keggin ion
KW - Polyoxometalates
KW - Self-assembly
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-546823
SN - 0947-6539
VL - 28
IS - 27
SP - 1
EP - 7
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-54682
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rautenberg, Max
A1 - Gernhard, M.
A1 - Radnik, Jörg
A1 - Witt, Julia
A1 - Roth, C.
A1 - Emmerling, Franziska
T1 - Mechanochemical synthesis of fluorine-containing Co-doped zeolitic imidazolate frameworks for producing electrocatalysts
N2 - Catalysts derived from pyrolysis of metal organic frameworks (MOFs) are promising candidates to replace expensive and scarce platinum-based electrocatalysts commonly used in polymer electrolyte membrane fuel cells. MOFs contain ordered connections between metal centers and organic ligands. They can be pyrolyzed into metal- and nitrogen-doped carbons, which show electrocatalytic activity toward the oxygen reduction reaction (ORR). Furthermore, metal-free heteroatom-doped carbons, such as N-F-Cs, are known for being active as well. Thus, a carbon material with Co-N-F doping could possibly be even more promising as ORR electrocatalyst. Herein, we report the mechanochemical synthesis of two polymorphs of a zeolitic imidazole framework, Co-doped zinc 2-trifluoromethyl-1H-imidazolate (Zn0.9Co0.1(CF3-Im)2). Time-resolved in situ X-ray diffraction studies of the mechanochemical formation revealed a direct conversion of starting materials to the products. Both polymorphs of Zn0.9Co0.1(CF3-Im)2 were pyrolyzed, yielding Co-N-F containing carbons, which are active toward electrochemical ORR.
KW - Mechanochemistry
KW - Metal-organic-frameworks
KW - Nobel-metal free electrocatalysis
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-546833
SN - 2296-2646
VL - 10
IS - 840758
SP - 1
EP - 13
PB - Frontiers Media
CY - Lausanne
AN - OPUS4-54683
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Gugin, Nikita
A1 - Villajos Collado, José Antonio
A1 - Feldmann, Ines
A1 - Emmerling, Franziska
T1 - Mix and wait – a relaxed way for synthesizing ZIF-8
N2 - Herein we report the synthesis of a zeolitic imidazolate framework (ZIF-8) by an easy “mix and wait” procedure. In a closed vial, without any interference, the mixture of 2-methylimidazole and basic zinc carbonate assembles into the crystalline product with approx. 90% conversion after 70 h. The reaction exhibits sigmoidal kinetics due to the self-generated water which accelerates the reaction.
KW - In-situ analysis
KW - Mechanochemistry
KW - MOF
KW - Synthesis
KW - ZIF-8
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-546841
VL - 12
SP - 8940
EP - 8944
PB - Royal Society of Chemistry
AN - OPUS4-54684
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Accelerated materials discovery with data analysis and machine learning
N2 - Talk on my research on machine-learning and automation for students of TU Berlin
T2 - TU Berlin Seminar
CY - Online meeting
DA - 24.01.2022
KW - Automation
KW - High-throughput
KW - DFT
PY - 2022
AN - OPUS4-54686
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Emmerling, Franziska
A1 - Martins, Ines
T1 - Carbamazepine Dihydroxybenzoic Acid Cocrystals: Exploring Packing Interactions and Reaction Kinetics
N2 - Herein, we present the mechanochemical formation of three new cocrystals containing the active pharmaceutical ingredient carbamazepine and dihydroxybenzoic acids as coformers (CBZ:2,4-DHBA 1:1, CBZ:2,5-DHBA 1:1, and CBZ:2,6-DHBA 1:1). Rietveld methods were used for three different purposes: (i) refining all structures solved using powder X-ray diffraction, (ii) performing a quantitative phase analysis of the diffraction data collected from ex situ mechanochemical reactions at different milling times, and (iii) determining the cocrystallization kinetic profiles. The rate of cocrystallization was found to be higher for the formation of CBZ:2,4-DHBA and CBZ:2,6-DHBA, reaching an equilibrium after 600 s of milling. In the case of CBZ:2,5-DHBA a short induction period of 20 s was detected prior to the start of the reaction and an equilibrium was reached after 1200 s. An empirical trend between the rate of cocrystallization and the structural complexity of the cocrystal product was found. The slowest cocrystallization rate observed for CBZ:2,5-DHBA corresponds to the crystal structure deviating substantially from the hydrogen-bonding motif found in the reactants.
KW - Mechanochemistry
KW - In situ real-time monitoring
KW - Kinetics
PY - 2021
U6 - https://doi.org/10.1021/acs.cgd.1c00902
VL - 21
IS - 12
SP - 6961
EP - 6970
PB - ACS Publications
AN - OPUS4-54407
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - New chemical understanding with the help of automation and highthroughput computations
N2 - High-throughput computations are nowadays an established way to suggest new candidate materials for applications to experimentalists. Due to new packages for automation and access to databases of computed materials properties, these studies became more and more complex over the last years. Besides suggesting new candidate materials for applications, they also offer a way to understanding the materials properties based on chemical bonds. For example, we have recently used orbital-based bonding analysis to understand the results of high-throughput studies for spintronic materials, ferroelectric materials and photovoltaic materials in detail. To do so, we have developed Python tools for high-throughput bonding analysis with the programs VASP and Lobster (see www.cohp.de). They are based on the Python packages pymatgen, atomate, and custodian. This implementation will be discussed within the talk. We also expect that these tools offer possibilities to arrive at new descriptors based on chemical bonds for materials properties.
T2 - High-throughput workflows for materials science with the Atomic Simulation Environment (ASE) and Fireworks
CY - Lyngby, Denmark
DA - 15. November 2021
KW - Automation
KW - High-throughput computations
KW - DFT
PY - 2021
AN - OPUS4-53840
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Michalchuk, Adam
A1 - Emmerling, Franziska
T1 - Time-Resolved InSitu Monitoring of Mechanochemical Reactions
N2 - Mechanochemical transformations offer environmentally benign synthesis routes, whilst enhancing both the speed and selec-tivity of reactions. In this light, mechanochemistry promises to trans-form the way in which chemistry is done in both academia and indus-try but is greatly hindered by a current lack in mechanistic understand-ing. The continued development and use of time-resolved in situ(TRIS) approaches to monitor mechanochemical reactions provides a new dimension to elucidatethese fascinating transformations. We here discuss recent trends in method development that have pushed the boundaries of mechanochemical research. New features of mech-anochemical reactions obtained by TRIS techniques are subse-quently discussed, shedding light on how different TRISapproaches have beenused. Emphasis is placed on the strength of combining complementary techniques. Finally, we outline our views for the po-tential of TRIS methods in mechanochemical research, towards es-tablishing a new, environmentally benign paradigm in the chemical sciences
KW - Mechanochemistry
KW - Material synthesis
KW - Green chemistry
PY - 2022
U6 - https://doi.org/10.1002/anie.202117270
SN - 1433-7851
SP - 1
EP - 15
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-54321
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - McMonagle, C. J.
A1 - Michalchuk, Adam
A1 - Chernyshov, D.
T1 - FOX-7 high-energy-density material: Thermal expansion and phase transitions revisited
N2 - Variable-temperature single-crystal diffraction experiments treated with the Gandolfi method reveal the detailed temperature evolution of the unit-cell dimensions, structural transformations and the phase co-existence of the energetic material FOX-7. Two first-order phase transitions are observed accompanied by abrupt changes in volume and unit-cell dimensions. The thermal expansion is found to be linear for all three phases, albeit highly anisotropic. Moreover, the experimental thermal expansion coefficients differ from those predicted from literature atomistic simulations.
KW - Energetic materials
KW - Thermal expansion
KW - Gandolfi method
KW - Phase transition
KW - Variable temperature
PY - 2022
U6 - https://doi.org/10.1107/S2052520621013299
SN - 2052-5206
VL - 78
IS - 1
SP - 91
EP - 95
PB - Wiley-Blackwell
CY - Oxford
AN - OPUS4-54286
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Casali, C.
A1 - Feiler, Torvid
A1 - Heilmann, Maria
A1 - Braga, D.
A1 - Emmerling, Franziska
A1 - Grepioni, F.
T1 - Too much water? Not enough? In situ monitoring of the mechanochemical reaction of copper salts with dicyandiamide
N2 - n situ monitoring of mechanochemical reactions between dicyandiamide (DCD) and CuX2 salts (X = Cl−, NO3−), for the preparation of compounds of agrochemical interest, showed the appearance of a number of phases. It is demonstrated that milling conditions, such as the amount of water added in wet grinding and/or the milling frequency, may affect the course of the mechanochemical reactions, and drive the reaction towards the formation of different products. It has been possible to discover by in situ monitored experiments two novel crystalline forms, namely the neutral complexes [Cu(DCD)2(OH2)2(NO3)2] (2) and [Cu(DCD)2(OH2)Cl2]·H2O (4), in addition to the previously known molecular salt [Cu(DCD)2(OH2)2][NO3]2·2H2O (1, DIVWAG) and neutral complex [Cu(DCD)2(OH2)Cl2] (3, AQCYCU), for which no synthesis conditions were available. Compounds 2 and 4 were fully characterized via a combination of solid-state techniques, including X-ray diffraction, Raman spectroscopy and TGA.
KW - Mechanochemistry
KW - In situ
PY - 2022
U6 - https://doi.org/10.1039/d1ce01670a
VL - 24
IS - 6
SP - 1292
EP - 1298
PB - RSC
AN - OPUS4-54344
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Heilmann, Maria
A1 - Prinz, Carsten
A1 - Bienert, Ralf
A1 - Wendt, R.
A1 - Kunkel, B.
A1 - Radnik, Jörg
A1 - Hoell, A.
A1 - Wohlrab, S.
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Emmerling, Franziska
T1 - Size-Tunable Ni–Cu Core–Shell Nanoparticles—Structure, Composition, and Catalytic Activity for the Reverse Water–Gas Shift Reaction
N2 - A facile and efficient methodology is described for the solvothermal synthesis of size-tunable, stable, and uniform NiCu core–shell nanoparticles (NPs) for application in catalysis. The diameter of the NPs is tuned in a range from 6 nm to 30 nm and to adjust the Ni:Cu ratio from 30:1 to 1:1. Furthermore, the influence of different reaction parameters on the final NPs is studied. The NPs are structurally characterized by a method combination of transmission electron microscopy, anomalous small-angle X-ray scattering, X-ray absorption fine structure, and X-ray photoelectron spectroscopy. Using these analytical methods, it is possible to elucidate a core–shell–shell structure of all particles and their chemical composition. In all cases, a depletion from the core to the shell is observed, with the core consisting of NiCu alloy, surrounded by an inner Ni-rich shell and an outer NiO shell. The SiO2-supported NiCu core–shell NPs show pronounced selectivity of >99% for CO in the catalytic reduction of CO2 to CO using hydrogen as reactant (reverse water–gas shift reaction) independent of size and Ni:Cu ratio.
KW - Nanoparticles
KW - Core-shell
KW - Catalysis
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-543606
SN - 1438-1656
SP - 1
EP - 13
PB - Wiley VCH
AN - OPUS4-54360
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Lakshmipathi, M.
A1 - Tothadi, S.
A1 - Emmerling, Franziska
A1 - Bhattacharya, Biswajit
A1 - Ghosh, S.
T1 - Different mechanical responses of dimorphic forms of Anthracene Schiffbase crystal
N2 - We obtained concomitant dimorphic forms of Anthracene Schiffbase (N-(anthracen-9-yl methylene)-2,5- dichloroaniline) from hexane solvent. Two polymorphs can be differentiated by their morphology and mechanical properties. One form is long acicular type and elastically bendable while another form is block shaped and brittle in nature. Mechanical property is attributed to underlying crystal packing. Hirsh- feld analysis and energy framework calculations were done to corroborate structure-property correlation of two forms.
KW - Elasticity
KW - Mechanical properties
KW - Anthracene schiff base
KW - Dimorphs
PY - 2021
U6 - https://doi.org/10.1016/j.molstruc.2021.132182
VL - 1252
SP - 1
EP - 8
PB - Elsevier B.V.
AN - OPUS4-54356
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - In situ investigations of mechanochemical processes
N2 - Overview of the present BAM activities in the field of in situ analytics of mechanochemical processes. Recent results for the synthesis of metal organic frameworks and cocrystals are presented.
T2 - HZB Seminar
CY - Online meeting
DA - 21.01.2022
KW - Mechanochemistry
KW - In situ real-time monitoring
PY - 2022
AN - OPUS4-54296
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Belenguer, A
A1 - Michalchuk, Adam
A1 - Lampronti, G
A1 - Sanders, J
T1 - Using solid catalysts in disulfide-based dynamic combinatorial solution- and mechano-chemistry
N2 - We here show for the first time that solid amines can act as catalysts for disulfide-based dynamic combinatorial chemistry by ball mill grinding. The mechanochemical Equilibrium for the two disulfide reactions studied is reached within one to three hours using ten different amine catalysts. This contrasts with the weeks to months to achieve solution equilibrium for most solid amine catalysts at 2%M at 2mM concentration in a suitable solvent. The final mechanochemical equilibrium is independent of the catalyst used, but varies with other ball mill grinding factors such as the presence of traces of solvent. The different efficiencies of the amines tested are discussed.
KW - Mechanochemistry
KW - Green chemistry
KW - Catalysis
PY - 2022
U6 - https://doi.org/10.1002/cssc.202102416
SN - 1864-5631
VL - 15
IS - 3
SP - 1
EP - 10
PB - Wiley
AN - OPUS4-53930
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Casali, L.
A1 - Broll, V.
A1 - Ciurili, S.
A1 - Braga, D.
A1 - Emmerling, Franziska
A1 - Gepioni, F.
T1 - Facilitating Nitrification Inhibition through Green, Mechanochemical Synthesis of a Novel Nitrapyrin Complex
N2 - Nitrapyrin (NP) is applied to cultivated soils to inhibit the enzymatic activity of ammonia monooxygenase (AMO), but its poor aqueous solubility and high volatility severely limit its application. β-Cyclodextrin (β-CD) is commonly used to form inclusion complexes with hydrophobic molecules, improving water solubility and stability upon complexation. Here we report on the mechanochemical synthesis of the inclusion complex β-CD·NP, characterized via a combination of solid-state techniques, including exsitu and in situ X-ray diffraction, Raman and NMR spectroscopies, transmission electron microscopy, and energy dispersive X-ray spectroscopy. The pure inhibitor NP was also structurally characterized. The β-CD·NP complex presents improved solubility and thermal stability, and still inhibits the enzymatic activity of AMO with high efficacy. All results indicate that the inclusion of NP into β-CD represents a viable route for the preparation of a novel class of inhibitors, with improved properties related to stability, water solubility, and good inhibition activity.
KW - Mechanochemistry
KW - Nitrification
PY - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-537154
VL - 21
IS - 10
SP - 5792
EP - 5799
PB - ACS Publications
AN - OPUS4-53715
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - Shaken not stirred: enhancing the flavor of mechanochemistry
N2 - Mechanochemistry is increasingly used for synthesizing soft matter materials including metal organic compounds and cocrystals.1 The ever-increasing interest in this method is contrasted by a limited mechanistic understanding of the mechanochemical reactivity and selectivity. Time-resolved in situ investigations of milling reactions provide direct insights in the underlying mechanisms.2-4 We recently introduced different setups enabling in situ investigation of mechanochemical reactions using synchrotron XRD combined with Raman spectroscopy and thermography. The presented setup allows the detection of crystalline, amorphous, eutectic, and liquid intermediates. Furthermore, the chemical composition of the reaction mixture was found to be directly correlated with changes in the temperature profile of the reaction. The resulting deeper kinetic and thermodynamic understanding of milling processes is the key for future optimization of mechanochemical syntheses. In this contribution, we will discuss our recent results investigating the formation of (polymorphic) cocrystals and coordination polymers.2,3,5 Our results indicate that in situ investigation of milling reactions offer a new approach to tune and optimize mechanochemical syntheses.
T2 - BCA/BACG joint spring meeting
CY - Online meeting
DA - 29.03.2021
KW - Mechanochemistry
KW - Cocrystals
KW - Crystal Engineering
PY - 2021
AN - OPUS4-53995
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - Shaken not stirred: in situ investigations of mechanochemical processes
N2 - Mechanochemistry has emerged as one of the most interesting synthetic protocols to produce new materials. The development of mechanochemistry as a synthetic method is supported by excellent research by many groups worldwide in a wide range of applications. The potential of mechanochemistry is also reflected in the inclusion in IUPAC’s 10 chemical innovations that will change our world’.[1] Solvent-free methodologies lead to unique chemical processes during synthesis with the consequent formation of martials with new properties.2 In this contribution, we will discuss our recent results investigating the formation of (polymorphic) cocrystals, coordination polymers, metal oxides and metal nanoparticles.[3-8] We introduced different setups enabling in situ investigation of mechanochemical reactions using synchrotron XRD combined with Raman spectroscopy and thermography.
T2 - Deutsche Kristallzüchtertagung
CY - Berlin, Germany
DA - 06.10.2021
KW - Mechanochemistry
KW - In situ real-time monitoring
KW - Crystal
PY - 2021
AN - OPUS4-53996
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - Scientific Writing - best practice tools
N2 - Personal view of an experienced writer on how to write a paper.
T2 - MatchingCamp 2021
CY - Bad Belzig, Germany
DA - 08.11.2021
KW - Writing
PY - 2021
AN - OPUS4-53999
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Lee, P.-W.
A1 - Kaynak, T.
A1 - Al-Sabbagh, Dominik
A1 - Emmerling, Franziska
A1 - Schalley, C.
T1 - Effect of Perfluorinated Side-Chain Length on the Morphology, Hydrophobicity, and Stability of Xerogel Coatings
N2 - Superhydrophobic surfaces can be quickly formed with supramolecular materials. Incorporating low-molecular-weight gelators (LMWGs) with perfluorinated chains generates xerogel coatings with low surface energies and high roughness. Here, we examine and compare the properties of the xerogel coatings formed with eight different LMWGs. These LMWGs all have a trans-1,2-diamidocyclohexane core and two perfluorinated ponytails, whose lengths vary from three to ten carbon atoms (CF3 to CF10). Investigation of the xerogels aims to provide in-depth information on the chain length effect. LMWGs with a higher degree of fluorination (CF7 to CF10) form superhydrophobic xerogel coatings with very low surface energies. Scanning electron microscopy images of the coatings show that the aggregates of CF5 and CF7 are fibrous, while the others are crystal-like. Aggregates of CF10 are particularly small and further assemble into a porous structure on the micrometer scale. To test their stabilities, the xerogel coatings were flushed multiple times with a standardized water flush test. The removal of material from the surface in these flushes was monitored by a combination of the water contact angle, contact angle hysteresis, and coating thickness measurements. A new method based on image processing techniques was developed to reliably determine the change of the coating thickness. The CF7, CF9, and CF10 surfaces show consistent hydrophobicity and coating durability after repetitive flushing tests. The length of the perfluorinated side chains thus has a significant effect on the morphology of the deposited xerogel coatings, their roughness, and, in consequence, their hydrophobicity and mechanical durability.
KW - Coating materials
KW - Amorphous materials
KW - Hydrophobicity
KW - Materials Stability
PY - 2021
U6 - https://doi.org/10.1021/acs.langmuir.1c02341
SN - 1520-5827
VL - 37
IS - 49
SP - 14390
EP - 14397
PB - ACS Publications
AN - OPUS4-54071
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Accelerated Materials Discovery Based on Data Analysis and Machine Learning
N2 - The stability of materials is a very important property for materials discovery. In recent years, we have explored several approaches for advancing the prediction of the stability of crystals (e.g., classical chemical heuristics and machine-learned interatomic potentials). For example, we have assessed a famous chemical heuristic – the Pauling rules – regarding their usefulness for structure prediction. They are only of limited predictive power, i.e. the rules 2 to 5 only work for 13 % of all tested oxides. Furthermore, we have shown that machine-learned interatomic potentials can be used to predict phonon properties of a range of silicon allotropes accurately and, therefore, they can also be used to assess the dynamic stability of materials. To do so, we have developed new schemes to build reference databases for machine learned interatomic potentials.
T2 - PACRIM & GOMD 2021
CY - Online meeting
DA - 13.12.2021
KW - Data analysis
KW - Machine learning
KW - High-throughput computations
PY - 2021
AN - OPUS4-54088
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Automation in Computational Materials Science
N2 - This lecture illustrated the current state of automation in the field of computational materials science based on recent examples from my research.
T2 - NOA Lecture Series FSU Jena
CY - Jena, Germany
DA - 02.11.2021
KW - Data analysis
KW - Machine learning
KW - High-throughput computations
PY - 2021
AN - OPUS4-54089
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Feiler, Torvid
A1 - Michalchuk, Adam
A1 - Schröder, V.
A1 - List-Kratochvil, E.
A1 - Emmerling, Franziska
A1 - Bhattacharya, Biswajit
T1 - Elastic Flexibility in an Optically Active Naphthalidenimine-Based Single Crystal
N2 - Organic single crystals that combine mechanical flexibility and optical properties are important for developing flexible optical devices, but examples of such crystals remain scarce. Both mechanical flexibility and optical activity depend on the underlying crystal packing and the nature of the intermolecular interactions present in the solid state. Hence, both properties can be expected to be tunable by small chemical modifications to the organic molecule. By incorporating a chlorine atom, a reportedly mechanically flexible crystal of (E)-1-(4-bromo-phenyl)iminomethyl-2-hydroxylnaphthalene (BPIN) produces (E)-1-(4-bromo-2-chloro-phenyl)iminomethyl-2-hydroxyl-naphthalene (BCPIN). BCPIN crystals show elastic bending similar to BPIN upon mechanical stress, but exhibit a remarkable difference in their optical properties as a result of the chemical modification to the backbone of the organic molecule. This work thus demonstrates that the optical properties and mechanical flexibility of molecular materials can, in principle, be tuned independently.
KW - Elastic Crystal
PY - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-539040
VL - 11
IS - 11
SP - 1397
PB - MDPI
AN - OPUS4-53904
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Feiler, Torvid
A1 - Bhattacharya, Biswajit
A1 - Michalchuk, Adam
A1 - Rhim, S.-Y.
A1 - Schröder, V.
A1 - List-Kratochvil, E.
A1 - Emmerling, Franziska
T1 - Tuning the mechanical flexibility of organic molecular crystal by polymorphism for flexible optical waveguide
N2 - Crystalline molecular materials are usually brittle and are prone to break into pieces upon external mechanical force. This fragility poses challenges for their application in next-generation technologies, including sensors, synthetic tissues, and advanced opto-electronics. The recent discovery of mechanical flexibility in single crystals of molecular materials has solved this issue and enable the design of smart flexible device technologies. Plastic crystals can be deformed permanently. This behavior is based on anisotropic molecular arrangements and the existence of facile slip planes which allow a permanent motion within the lattice. In contrast, elastic crystals can be deformed, but regain the original structure when the force is removed. This phenomenon is related to energetically isotropic molecular packing. Here we report 4-bromo-6-[(6-chlorolpyridin-2-ylimino)methyl]phenol (BCMPMP) as a promising candidate for future waveguide technologies. It turns out that BCMPMP has two different polymorphs with distinct optical and mechanical properties. Form I crystallizes in the orthorhombic space group Pca21 and shows brittle behavior. This structure exhibit very weak emission at 605 nm (λex = 425 nm) together with a low fluorescence quantum yield (Φ = 0.4 %). On the other hand, form II (monoclinic space group P21/c) has a large plastic regime and a bright emission at 585 nm (λex = 425 nm; Φ = 8.7 %). Based on its improved mechanical and optical properties, form II was explored as a bendable optical waveguide. Light was successfully propagated through a straight-shaped and mechanically deformed BCMPMP crystal. Depending on the light source, active or passive waveguiding could be achieved. So BCMPMP can also be used as a flexible wavelength filter.
T2 - International School of Crystallography in Erice
CY - Online meeting
DA - 30.05.2021
KW - Flexible crystals
KW - Polymorphism
KW - Waveguide
PY - 2021
AN - OPUS4-53905
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Feiler, Torvid
A1 - Bhattacharya, Biswajit
A1 - Michalchuk, Adam
A1 - Rhim, S.-Y.
A1 - Schröder, V.
A1 - List-Kratochvil, E.
A1 - Emmerling, Franziska
T1 - Polymorphic tuning of a flexible organic crystal optical waveguide
N2 - Crystalline molecular materials are usually brittle and are prone to break upon external mechanical force. This fragility poses challenges for their application in next-generation technologies, including sensors, synthetic tissues, and advanced opto-electronics. The recent discovery of mechanical flexibility in single crystals of molecular materials has solved this problem and enable the design of smart flexible device technologies. Mechanical flexibility of organic crystals can be tuned by altering the weak interactions in the crystal structure, for examples through polymorphism. Here we report 4-bromo-6-[(6-chlorolpyridin-2-ylimino)methyl]phenol (BCMPMP) as a promising candidate for future waveguide technologies. It turns out that BCMPMP has two different polymorphs with distinct optical and mechanical properties. Form I shows brittle behavior under mechanical stress and exhibits very weak emission at 605 nm (λex = 425 nm) together with a low fluorescence quantum yield (Φ = 0.4 %).In contrast, Form II has a large plastic (irreversible bending) regime and a bright emission at 585 nm (λex = 425 nm; Φ = 8.7 %). Making use of favorable mechanical fexiblity and optical properties, form II was explored as a bendable optical waveguide. Light was successfully propagated through a straight-shaped and mechanically deformed BCMPMP crystal. Depending on the light source, active or passive waveguiding could be achieved. So BCMPMP can also be used as a flexible wavelength filter.
T2 - Congress of the International Union of Crystallography - IUCr 2021
CY - Online meeting
DA - 14.08.2021
KW - Flexible crystals
KW - Polymorphism
KW - Waveguide
PY - 2021
AN - OPUS4-53906
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Feiler, Torvid
A1 - Bhattacharya, Biswajit
A1 - Michalchuk, Adam
A1 - Rhim, S.-Y.
A1 - Schröder, V.
A1 - List-Kratochvil, E.
A1 - Emmerling, Franziska
T1 - Mechanically flexible crystals: materials for new generation of responsive materials
N2 - Based on the nature of the deformation, molecular crystals can be defined as being plastically (irreversible) or elastically (reversible)bendable. The mechanical response of crystals is thereby directly related to they structure.The structural elements required for a specific mechanical behavior are known, so that compounds with these properties can be synthesized by applying the rules of crystal engineering.
T2 - Berlin Science Week
CY - Berlin, Germany
DA - 01.11.2021
KW - Flexible crystals
PY - 2021
AN - OPUS4-53907
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Feiler, Torvid
A1 - Bhattacharya, Biswajit
A1 - Michalchuk, Adam
A1 - Rhim, S.-Y.
A1 - Schröder, V.
A1 - List-Kratochvil, E.
A1 - Emmerling, Franziska
T1 - Optimierung der mechanischen Eigenschaften eines organischen Kristalles durch Polymorphismus für die Anwendung als flexibler Waveguide
N2 - Kristalle sind in der Regel spröde und neigen dazu, bei mechanischer Belastung zu brechen. Dieses Verhalten schränkt ihre Anwendungsmöglichkeiten stark ein. Durch die Entdeckung von mechanischer Flexibilität in Kristallen wurde dieses Problem gelöst. Je nach Art der Verformung können Kristalle in plastisch (irreversibel) oder elastisch (reversibel) biegbar unterteilt werden. Die Verbindung 4-Brom-6-[(6-chlorpyridin-2-ylimino)methyl]phenol (BCMPMP) ist ein vielversprechender Kandidat für die Anwendung als flexibler Waveguide. BCMPMP hat zwei verschiedene Polymorphe mit unterschiedlichen optischen und mechanischen Eigenschaften. Die spröden Kristalle der Form I zeigen eine sehr schwache Emission bei 605 nm (λex = 425 nm; Photolumineszenz-Quantenausbeute Φ = 0,4 %). Im Gegensatz dazu zeigt die plastische Form II eine starke Emission bei 585 nm (λex = 425 nm; Φ = 8,7 %). Aufgrund der mechanischen Flexibilität wurde die Eignung der Form II als Waveguide untersucht.
T2 - Tag der Chemie 2021
CY - Online meeting
DA - 06.07.2021
KW - Flexible crystals
KW - Polymorphism
KW - Waveguide
PY - 2021
AN - OPUS4-53908
LA - mul
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Heilmann, Maria
A1 - Simões, R. G.
A1 - Bernardes, C. E. S.
A1 - Ramisch, Yen
A1 - Bienert, Ralf
A1 - Röllig, Matthias
A1 - Emmerling, Franziska
A1 - Minas da Piedade, M. E.
T1 - Real-Time In situ XRD Study of Simvastatin Crystallization in Levitated Droplets
N2 - Simvastatin (SV) is an important active pharmaceutical ingredient (API) for treatment of hyperlipidemias, which is known to exist in different crystalline and amorphous phases. It is, therefore, an interesting model to investigate how the outcome of evaporative crystallization in the contactless environment of an acoustically levitated droplet may be influenced by key experimental conditions, such as temperature, solvent properties (e.g., polarity and hygroscopicity), and dynamics of the evaporation process. Here, we describe a real-time and in situ study of simvastatin evaporative crystallization from droplets of three solvents that differ in volatility, polarity, and protic character (acetone, ethanol, and ethyl acetate). The droplet monitorization relied on synchrotron X-ray diffraction (XRD), Raman spectroscopy, imaging, and thermographic analysis. A pronounced solvent-dependent behavior was observed. In ethanol, a simvastatin amorphous gel-like material was produced, which showed no tendency for crystallization over time; in ethyl acetate, a glassy material was formed, which crystallized on storage over a two-week period to yield simvastatin form I; and in acetone, form I crystallized upon solvent evaporation without any evident presence of a stable amorphous intermediate. The XRD and Raman results further suggested that the persistent amorphous phase obtained from ethanol and the amorphous precrystallization intermediate formed in ethyl acetate were similar. Thermographic analysis indicated that the evaporation process was accompanied by a considerable temperature decrease of the droplet surface, whose magnitude and rate correlated with the solvent volatility (acetone > ethyl acetate > ethanol). The combined thermographic and XRD results also suggested that, as the cooling effect increased, so did the amount of residual water (most likely captured from the atmosphere) remaining in the droplet after the organic solvent was lost. Finally, the interpretation of the water fingerprint in the XRD time profiles was aided by molecular dynamics simulations, which also provided insights into the possible role of H2O as an antisolvent that facilitates simvastatin crystallization.
KW - Simvastatin
KW - In-situ
KW - API
KW - Crystallization
PY - 2021
U6 - https://doi.org/10.1021/acs.cgd.1c00509
SN - 1528-7483
VL - 21
IS - 8
SP - 4665
EP - 4673
PB - ACS Publications
AN - OPUS4-53663
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Stawski, Tomasz
A1 - Van Driessche, A. E. S.
T1 - The structure of amorphous calcium sulfate and its role in the nucleation pathway and final mesostructure of CaSO 4 phases
N2 - In recent years, we have come to appreciate the astounding intricacy of the formation process of minerals from ions in aqueous solutions. In this context, a number of studies have already revealed that nucleation in the CaSO4-H2O system is non-classical, where the formation of the different crystalline phases involves several steps including a common amorphous precursor. In this contribution a holistic view of the formation mechanism of gypsum and bassanite from solution will be presented.
In short, our in situ and time-resolved scattering data demonstrate that calcium sulfate precipitation starts with the formation and aggregation of well-defined sub-3 nm primary species. These species constitute building “bricks'' of an amorphous precursor phase. We characterised the “bricks” by combining information obtained at different length-scales accessible at the mesoscale (from small-angle scattering) and at the atomic-length-scale (wide-angle scattering and high-energy diffraction). From these scattering data we derived pair distribution functions of the clusters and restricted their external shapes and dimensions. This allowed us to propose a structure of the primary species and to explore their dynamic properties with unbiased MD simulations using polarizable force fields. The formation of the amorphous phase involves the aggregation of these small primary species into larger disordered aggregates exhibiting “brick-in-the-wall” structure. The actual crystallisation occurs by the restructuring and coalescence of the “bricks” into a given calcium sulfate phase depending on the thermodynamic conditions of the solution. Importantly, these rearrangement processes by no means continue until a (nearly-)perfect homogeneous single crystal is obtained. Instead they come to a stop or at least significantly slow down. Such a process thus yields a final imperfect mesocrystal, composed of smaller domains rather than a continuous crystal structure, within which the domains are separated by an amorphous calcium sulfate phase.
T2 - Goldschmidt Virtual 2021
CY - Online meeting
DA - 04.07.2021
KW - Amorphous calcium sulfate
KW - Scattering
KW - SAXS/WAXS
PY - 2021
UR - https://2021.goldschmidt.info/goldschmidt/2021/meetingapp.cgi/Paper/3847
AN - OPUS4-53621
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - George, Janine
T1 - Automation in DFT-based computational materials science
N2 - Automation simplifies the use of computational materials science software and makes it accessible to a wide range of users. This enables high-throughput calcula-tionsand makesiteasier for non-specialists to enter computational materials science. However, in-creasing automation also poses threats that should be considered while interacting with automated procedures.
KW - DFT
KW - Automation
KW - High-throughput computations
PY - 2021
U6 - https://doi.org/10.1016/j.trechm.2021.07.001
SN - 2589-5974
VL - 3
IS - 9
SP - 697
EP - 699
PB - Elsevier
CY - Amsterdam
AN - OPUS4-53127
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Lampronti, G.
A1 - Michalchuk, Adam
A1 - Mazzeo, P.
A1 - Belenguer, Ana
A1 - Sanders, J. K. M.
A1 - Bacchi, A.
A1 - Emmerling, Franziska
T1 - Changing the game of time resolved X-ray diffraction on the mechanochemistry playground by downsizing
N2 - Time resolved in situ (TRIS) monitoring has revolutionised the study of mechanochemical transformations but has been limited by available data quality. Here we report how a combination of miniaturised grinding jars together with innovations in X-ray powder diffraction data collection and state-of-the-art analysis strategies transform the power of TRIS synchrotron mechanochemical experiments. Accurate phase compositions, comparable to those obtained by ex situ measurements, can be obtained with small sample loadings. Moreover, microstructural parameters (crystal size and microstrain) can be also determined with high confidence. This strategy applies to all chemistries, is readily implemented, and yields high-quality diffraction data even using a low energy synchrotron source. This offers a direct avenue towards the mechanochemical investigation of reactions comprising scarce, expensive, or toxic compounds. Our strategy is applied to model systems, including inorganic, metal-organic, and organic mechanosyntheses, resolves previously misinterpreted mechanisms in mechanochemical syntheses, and promises broad, new directions for mechanochemical research.
KW - Mechanochemistry
KW - Synchrotron radiation
KW - Material synthesis
PY - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-535932
SN - 2041-1723
VL - 12
IS - 1
SP - 1
EP - 9
PB - Nature Publishing Group
CY - London
AN - OPUS4-53593
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Automation in Computational Materials Science
N2 - The talk „Automation in computational materials science“ deals with the current state of automation in the field of computational materials science. It illustrates how automation can, for example, be used to speed up the search for new ferroelectric materials and spintronic materials. Furthermore, it lists current tools for automation and challenges in the field.
T2 - SALSA School 2021
CY - Online meeting
DA - 16.09.2021
KW - Automation
KW - High-throughput
PY - 2021
AN - OPUS4-53483
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Rautenberg, Max
A1 - Gernhard, Marius
A1 - Roth, Christina
A1 - Emmerling, Franziska
T1 - Fluorination and co-doping of ZIF-8 by ball mill grinding for efficient oxygen reduction electrocatalysis
N2 - The oxygen reduction reaction (ORR) is a common process in a variety of electrochemical devices, like fuel cells and metal air batteries. The sluggish kinetics of the ORR require an electrocatalyst to pass this bottleneck.[1] Currently, the most used catalytical systems are platinum-based, with several drawbacks, such as the high cost, low availability, and deactivation by CO poisoning.[2] Efforts are made to develop efficient, durable and low cost catalysts to promote the commercialization of fuel cells.
Non-precious metal catalysts are promising candidates for efficient ORR catalysis. It has been shown that pyrolyzing metal organic frameworks (MOFs) under inert conditions yields carbon-rich materials, with evenly distributed metal sites, which possess promising electrocatalytic activity.[3] One widely used type of MOF as ORR catalyst precursors is the zeolitic imidazole framework (ZIF) where metal cations are linked through imidazole-based ligands. Their porous nature is partially retained after carbonization, making MOFs very suitable precursor materials.
Herein we report the mechanochemical synthesis and structural analysis of Co-doped ZIF-8 (Zn), as well as two polymorphs (dense and prorous) of fluorinated Co-doped CF3-ZIF-8 (Zn). The samples showed electrochemical performance comparable to platinum after carbonization for 1 h at temperatures ranging between 850 – 1000°C.
T2 - XXV General Assembly and Congress of the International Union of Crystallography - IUCr 2021
CY - Prague, Czech Republic
DA - 14.08.2021
KW - PGM-free catalyst
KW - Oxygen Reduction Reaction
KW - Mechanochemistry
KW - MOFs
PY - 2021
AN - OPUS4-53535
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Rautenberg, Max
A1 - Gernhard, Marius
A1 - Low, Jian L.
A1 - Roth, Christina
A1 - Paulus, Beate
A1 - Emmerling, Franziska
T1 - Fluorine Modified ZIF 8 for Electrochemical Catalysis: Where does the Fluorine go?
N2 - Carbonization of fluorinated metal-organic frameworks (MOFs) should yield fluorinated nitrogen- and metal-doped carbons (F-NMCs), which are a combination of NMCs and fluorinated carbons, each promising electrocatalysts on their own. We synthesized two polymorphs of a fluorinated MOF by mechanical ball mill grinding, and carbonized them to yield potential electrocatalyt materials. The catalytical activity towards the oxygen reduction reaction (ORR) was examined, finding good activites. Simulations from a theoretic model helped assesing the stability of proposed catalytic sites and understanding the measured activites towards the ORR catalysis.
T2 - Online symposium of the CRC 1349 "fluorine-specific interactions"
CY - Online meeting
DA - 29.06.2021
KW - PGM-free catalyst
KW - Oxygen Reduction Reaction
KW - Mechanochemistry
KW - MOFs
KW - Computational chemistry
PY - 2021
AN - OPUS4-53538
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Rautenberg, Max
A1 - Gernhard, Marius
A1 - Roth, Christina
A1 - Emmerling, Franziska
T1 - Synthesis and characterization of fluorinated Co-Zn-Zeolitic imidazole frameworks for catalysis of the oxygen reduction reaction
N2 - The oxygen reduction reaction (ORR) is a common process in a variety of electrochemical devices, like fuel cells
and metal air batteries. The sluggish kinetics of the ORR require an electrocatalyst to pass this bottleneck.[1]
Currently, the most used catalytical systems are platinum-based, with several drawbacks, such as the high cost,
low availability, and deactivation by CO poisoning.[2] Efforts are made to develop efficient, durable and low cost
catalysts to promote the commercialization of fuel cells.
Non-precious metal catalysts are promising candidates for efficient ORR catalysis. It has been shown that
pyrolyzing metal organic frameworks (MOFs) under inert conditions yields carbon-rich materials, with evenly
distributed metal sites, which possess promising electrocatalytic activity.[3] One widely used type of MOF as ORR
catalyst precursors is the zeolitic imidazole framework (ZIF) where metal cations are linked through imidazolebased ligands.
Herein we report the mechanochemical synthesis, structural analysis and of Co-doped ZIF-8 (Zn), as well as its
fluorinated counterpart Co-doped CF3
-ZIF-8 (Zn). The samples showed electrochemical performance comparable
to platinum after carbonization for 1h at temperatures ranging between 850 – 1000°C.
T2 - 15th International conference on materials chemistry (MC15)
CY - Online meeting
DA - 12.07.2021
KW - PGM-free catalyst
KW - Oxygen Reduction Reaction
KW - Mechanochemistry
KW - MOFs
PY - 2021
AN - OPUS4-53539
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Martins, I.
A1 - Carta, M.
A1 - Haferkamp, Sebastian
A1 - Feiler, Torvid
A1 - Delogu, F.
A1 - Colacino, E.
A1 - Emmerling, Franziska
T1 - Mechanochemical N‑Chlorination Reaction of Hydantoin: In Situ Real-Time Kinetic Study by Powder X‑ray Diffraction and Raman Spectroscopy
N2 - Mechanochemistry has become a valuable tool for the synthesis of new molecules, especially in the field of organic chemistry. In the present work, we investigate the kinetic profile of the chlorination reaction of N-3-ethyl-5,5-dimethylhydantoin (EDMH) activated and driven by ball milling. The reaction has been carried out using 2 mm, 4 mm, 5 mm, 6 mm, and 8 mm ball sizes in a new small custom-made Perspex milling jar. The Crystal structure of the starting material EDMH and the 1-chloro-3-ethyl5,5′-dimethyl hydantoin (CEDMH) chlorination product was solved by single-crystal X-ray diffraction. The reaction was monitored, in situ and in real time, by both powder X-ray diffraction (PXRD) and Raman spectroscopy. Our kinetic data show that the reaction progress to equilibrium is similar at all milling ball sizes. The induction period is very short (between 10 and 40 s) when using 4 mm, 5 mm, 6 mm, and 8 mm balls. For the reaction performed with a 2 mm ball, a significantly longer induction period of 9 min was observed. This could indicate that an initial energy accumulation and higher mixing efficiency are necessary before the reaction starts. Using different kinetic models, we found that the amount of powder affected by critical loading conditions during individual impacts is significantly dependent on the ball size used. An almost linear correlation between the rate of the chemical transformations and the ball volume is observed.
KW - Mechanochemistry
KW - In situ real-time monitoring
KW - N-Chlorination
KW - Kinetics
KW - Hydantoin
KW - Powder X-ray diffraction
KW - Raman spectroscopy
PY - 2021
U6 - https://doi.org/10.1021/acssuschemeng.1c03812
VL - 9
IS - 37
SP - 12591
EP - 12601
AN - OPUS4-53541
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Souza, B.
A1 - Chauque, S.
A1 - de Oliveira, P.
A1 - Emmerling, Franziska
A1 - Torresi, R.
T1 - Mechanochemical optimization of ZIF-8/Carbon/S8 composites for lithium-sulfur batteries positive electrodes
N2 - The application of lithium-sulfur (Li-S) batteries is still limited by their rapid capacity fading. The pulverization of the sulfur positive electrode after the lithiation and the consequence dissolution of long chain polysulfides in organic solvents lead to the shuttle effect. To address these issues, here we report the mechanochemical preparation of ZIF-8 (Zeolitic Imidazole Framework-8)-based composites as sulfur hosts for positive electrodes in Li-S batteries. We studied different methods for the incorporation of conductive carbon. Also, the replacement of Zn2+ metal centers by other bivalent metals (Cu2+, Co2+ and Ni2+), enabled the preparation of other ZIF-8-based materials. The positive electrode ZIF-8/C/S8 showed initial discharges of 772 mA h g−1 while the pristine one, ZIF-8/S8, displayed 502 mA h g−1. The enhanced performance of 54% for ZIF-8/C/S8 indicates that the direct mechanochemical synthesis of ZIF-8 with conductive carbon is beneficial at initials charge/discharge process in comparison to traditional slurry preparation (ZIF-8/S8). Also, the Li2S6 absorption tests shows 87% of discoloration with ZIF-8/C/S8, confirming the better polysulfides absorption.
KW - Lithium-sulfur battery
KW - Metal organic frameworks
KW - ZIF-8
KW - Mechanochemistry
PY - 2021
U6 - https://doi.org/10.1016/j.jelechem.2021.115459
VL - 896
SP - 115459
PB - Elsevier B.V.
AN - OPUS4-53542
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Michalchuk, Adam
A1 - Rudic, S.
A1 - Pulham, C.
A1 - Morrison, C.
T1 - Predicting the impact sensitivity of a polymorphic high explosive: the curious case of FOX-7
N2 - The impact sensitivity (IS) of FOX-7 polymorphs is predicted by phonon up-pumping to decrease as layers of FOX-7 molecules flatten. Experimental validation proved anomalous owing to a phase transition during testing, raising questions regarding Impact sensitivity measurement and highlighting the need for models to predict IS of polymorphic energetic materials.
KW - Energetic materials
KW - Density functional theory
KW - Inelastic Neutron Scattering Spectroscopy
KW - Impact Sensitivity
PY - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-535558
SN - 1364-548X
VL - 57
IS - 85
SP - 11213
EP - 11216
PB - Royal Society of Chemistry
AN - OPUS4-53555
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Data-driven materials discovery and understanding
N2 - Developments in density functional theory (DFT) calculations, their automation and therefore easier access to materials data have enabled ab initio high-throughput searches for new materials for numerous applications. These studies open up exciting opportunities to find new materials in a much faster way than based on experimental work alone. However, performing density functional theory calculations for several thousand materials can still be very time consuming. The use of, for example, faster chemical heuristics and machine-learned interatomic potentials would allow to consider a much larger number of candidate materials. In addition to DFT based high-throughput searches, the seminar will discuss two possible ways to accelerate high-throughput searches.
Using data analysis on the structures and coordination environments of 5000 oxides, we were able to investigate a chemical heuristic – the famous Pauling rules – regarding its usefulness for the fast prediction of stable materials.
We have also investigated how machine-learned interatomic potentials can be used to accelerate the prediction of (dynamically) stable materials. The use of these potentials makes vibrational properties accessible in a much faster way than based on DFT. Our results based on a newly developed potential for silicon allotropes showed excellent agreement with DFT reference data (agreement of the frequencies within 0.1-0.2 THz).
In addition, we have successfully used high-throughput calculations in the search for new candidate materials for spintronic applications and ferroelectrics
T2 - ETSF Webinar
CY - Online meeting
DA - 25.06.2021
KW - High-throughput computations
KW - Data analysis
KW - Machine learning
PY - 2021
AN - OPUS4-52980
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Automatisierung in der Computerchemie
N2 - Im Vortrag wird der aktuelle Stand zur Automatisierung in der Computerchemie und der computergestützten Materialwissenschaft besprochen.
T2 - Online-Workshop des Fördervereins Chemieolympiade 2021
CY - Online meeting
DA - 19.06.2021
KW - Computergestützte Materialwissenschaft
KW - Automatisierung
KW - Hochdurchsatz
KW - Computerchemie
PY - 2021
AN - OPUS4-52981
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Battig, Alexander
A1 - Müller, Patrick
A1 - Bertin, Annabelle
A1 - Schartel, Bernhard
T1 - Hyperbranched Rigid Aromatic Phosphorus-Containing Flame Retardants for Epoxy Resins
N2 - A rigid aromatic phosphorus-containing hyperbranched flame retardant structure is synthesized from 10-(2,5 dihydroxyphenyl)-10H-9-oxa-
10-phosphaphenanthrene-10-oxide (DOPO-HQ), tris(4-hydroxyphenyl)phosphine oxide (THPPO), and 1,4-terephthaloyl chloride (TPC). The resulting poly-(DOPO-HQ/THPPO-terephthalate) (PDTT) is implemented as a flame retardant into an epoxy resin (EP) at a 10 wt% loading. The effects on EP are compared with those of the monomer DOPO-HQ and triphenylphosphine oxide (OPPh3) as low molar mass flame retardants. The glass transition temperature, thermal decomposition, flammability (reaction to small flame), and burning behavior of the thermosets are investigated using differential scanning calorimetry, thermogravimetric analysis, pyrolysis combustion flow calorimetry, UL 94-burning chamber testing, and cone calorimeter measurements.
Although P-contents are low at only 0.6 wt%, the study aims not at attaining V-0, but at presenting a proof of principle: Epoxy resinswith PDTT show promising fire performance, exhibiting a 25% reduction in total heat evolved (THE), a 30% reduction in peak heat release rate (PHRR) due to flame inhibition (21% reduction in effective heat of combustion (EHC)), and an increase in Tg at the same time. This study indicates that rigid aromatic hyperbranched polymeric structures offer a promising route toward multifunctional flame retardancy.
KW - Hyperbranched
KW - Aromatic
KW - Phosphorus
KW - Phosphine oxide
KW - DOPO
KW - Flame retardant
KW - Xpoxy resin
KW - Rigid
PY - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-525910
SN - 1439-2054
VL - 306
IS - 4
SP - 731
PB - Wiley
AN - OPUS4-52591
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Feiler, Torvid
A1 - Bhattacharya, Biswajit
A1 - Michalchuk, Adam
A1 - Rhim, S.-Y.
A1 - Schöder, V.
A1 - List-Kratochvil, E.
A1 - Emmerling, Franziska
T1 - Tuning the mechanical flexibility of organic molecular crystals by polymorphism for flexible optical waveguides
N2 - The ability to selectively tune the optical and the mechanical properties of organic molecular crystals offers a promising approach towards developing flexible optical devices. These functional properties are sensitive to crystallographic packing features and are hence expected to vary with polymorphic modification. Using as a model system the photoluminescent material 4-bromo-6-[(6-chloropyridin-2-ylimino)methyl]phenol (CPMBP), we herein demonstrate the simultaneous tuning of mechanical flexibility and photoluminescence properties via polymorphism. Two new polymorphic forms of CPMBP were obtained from a solution and fully characterised using a combination of experiments and density functional theory simulations. These polymorphic forms exhibit remarkably distinct mechanical properties and an order of magnitude difference in photoluminescence quantum yield. The mechanically plastic form has a higher quantum yield than the brittle polymorphic form. However, their photoluminescence emission profile is largely unaffected by the observed polymorphism, thereby demonstrating that the optical properties and bulk mechanical properties can in principle be tuned independently. By distinguishing between active (involving absorption and emission) and passive (involving no absorption) light propagation, the waveguiding properties of the plastic form of CPMBP (form II) were explored using the straight and bent crystals to highlight the potential applications of CPMBP in designing flexible optical devices. Our results demonstrated that polymorph engineering would be a promising avenue to achieve concurrent modulation of the optical and mechanical properties of photoluminescent molecular crystals for next-generation flexible optical device applications.
KW - Mechanochemistry
KW - Flexible
PY - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-532075
VL - 23
IS - 34
SP - 5815
EP - 5825
PB - Royal Society of Chemistry
CY - London
AN - OPUS4-53207
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Quiroz, J.
A1 - de Oliveira, P. F. M.
A1 - Shetty, S.
A1 - Oropeza, F.
A1 - Peña O’Shea, V.
A1 - Rodrigues, L.
A1 - Rodrigues, M.
A1 - Torresi, R.
A1 - Emmerling, Franziska
A1 - Camargo, P.
T1 - Bringing earth-abundant plasmonic catalysis to light: Gram-scale mechanochemical synthesis and tuning of activity by dual excitation of antenna and reactor sites
N2 - The localized surface plasmon resonance (LSPR) excitation in plasmonic nanoparticles (NPs) in the visible and near-infrared ranges is currently at the forefront of improving photocatalytic performances via plasmonic photocatalysis. One bottleneck of this field is that the NPs that often display the best optical properties in the visible and near-infrared ranges are based on expensive noble metals such as silver (Ag) and gold (Au). While earth-abundant plasmonic materials have been proposed together with catalytic metals in antenna–reactor systems, their performances remain limited by their optical properties. Importantly, the synthesis of plasmonic photocatalysts remains challenging in terms of scalability while often requiring several steps, high temperatures, and special conditions. Herein, we address these challenges by developing a one-pot, gram-scale, room-temperature synthesis of earth-abundant plasmonic photocatalysts while improving their activities beyond what has been dictated by the LSPR excitation of the plasmonic component. We describe the mechanochemical synthesis of earth-abundant plasmonic photocatalysts by using MoO3 (antenna) and Au (reactor) NPs as a proof-of-concept example and demonstrate that the dual plasmonic excitation of antenna and reactor sites enables the tuning of plasmonic photocatalytic performances toward the reductive coupling of nitrobenzene to azobenzene as a model reaction. In addition to providing a pathway to the facile and gram-scale synthesis of plasmonic photocatalysts, the results reported herein may open pathways to improved activities in plasmonic catalysis.
KW - MoO3
KW - Au nanoparticles
KW - Localized surface plasmon resonance
KW - Plasmonic photocatalysis
KW - Nitrobenzene reduction
PY - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-532089
VL - 9
IS - 29
SP - 9750
EP - 9760
PB - American Chemical Society
CY - Washington, DC
AN - OPUS4-53208
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Chapartegui-Arias, Ander
A1 - Raysyan, A.
A1 - Belenguer, A. M.
A1 - Jaeger, Carsten
A1 - Tchipilov, Teodor
A1 - Prinz, Carsten
A1 - Abad Andrade, Carlos Enrique
A1 - Beyer, S.
A1 - Schneider, Rudolf
A1 - Emmerling, Franziska
T1 - Tailored mobility in a zeolite imidazolate framework (ZIF) antibody conjugate
N2 - Zeolitic imidazolate framework (ZIF) hybrid fluorescent nanoparticles and ZIF antibody conjugates have been synthesized, characterized, and employed in lateral-flow immunoassay (LFIA). The bright fluorescence of the conjugates and the possibility to tailor their mobility gives a huge potential for diagnostic assays. An enzyme-linked immunosorbent assay (ELISA) with horseradish peroxidase (HRP) as label, proved the integrity, stability, and dispersibility of the antibody conjugates, LC-MS/MS provided evidence that a covalent link was established between these metal-organic frameworks and lysine residues in IgG antibodies.
KW - ZIF
KW - ELISA
PY - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-532096
SN - 0947-6539
SN - 1521-3765
VL - 27
IS - 36
SP - 9414
EP - 9421
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-53209
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Linberg, Kevin
A1 - Röder, Bettina
A1 - Al-Sabbagh, Dominik
A1 - Emmerling, Franziska
A1 - Michalchuk, Adam
T1 - Controlling polymorphism in molecular cocrystals by variable temperature ball milling
N2 - Mechanochemistry offers a unique opportunity to modify and manipulate crystal forms, often providing new products as compared with conventional solution methods. While promising, there is little known about how to control the solid form through mechanochemical means, demanding dedicated investigations. Using a model organic cocrystal system (isonicotinamide:glutaric acid), we here demonstrate that with mechanochemistry, polymorphism can be induced in molecular solids under conditions seemingly different to their conventional thermodynamic (thermal) transition point.
Whereas Form II converts to Form I upon heating to 363 K, the same transition can be initiated under ball milling conditions at markedly lower temperatures (348 K). Our results indicate that mechanochemical techniques can help to reduce the energy barriers to solid form transitions, offering new insights into controlling polymorphic forms. Moreover, our results suggest that the nature of mechanochemical transformations could make it difficult to interpret mechanochemical solid form landscapes using conventional equilibrium-based tools.
KW - Mechanochemistry
KW - Kinetics
KW - In situ
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-558878
SP - 1
EP - 16
PB - Royal Society of Chemistry
AN - OPUS4-55887
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Michalchuk, Adam
T1 - The Mechanochemical Excitation of Crystalline LiN3
N2 - Mechanochemical reactions are driven by the direct absorption of mechanical energy by a solid (often crystalline) material. Understanding how this energy is absorbed and ultimately causes a chemical transformation is essential for understanding the elementary stages of mechanochemical transformations. Using as a model system the energetic material LiN3 we here consider how vibrational energy flows through the crystal structure. By considering the compression response of the crystalline material we identify the partitioning of energy into an initial vibrational excitation. Subsequent energy flow is based on concepts of phonon–phonon scattering, which we calculate within a quasi-equilibrium model facilitated by phonon scattering data obtained from Density Functional Theory (DFT). Using this model we demonstrate how the moments (picoseconds) immediately following mechanical impact lead to significant thermal excitation of crystalline LiN3, sufficient to drive marked changes in its electronic structure and hence chemical reactivity. This work paves the way towards an ab initio approach to studying elementary processes in mechanochemical reactions involving crystalline solids.
KW - Energetic materials
KW - Ab initio simulation
KW - DFT
KW - Mechanochemistry
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-559310
SP - 1
EP - 20
PB - Royal Society of Chemistry
AN - OPUS4-55931
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mazzeo, P
A1 - Lampronti, G
A1 - Michalchuk, Adam
A1 - Belenguer, A
A1 - Bacchi, A
A1 - Emmerling, Franziska
T1 - Accurate extrinsic and intrinsic peak broadening modelling for time-resolved in situ ball milling reactions via synchrotron powder X-ray diffraction
N2 - The debate on the mechanisms which underpin mechanochemical reactions via ball mill grinding is still open. Our ability to accurately measure the microstructural (crystal size and microstrain) evolution of materials under milling conditions as well as their phase composition as a function of time is key to the in-depth understanding of the kinetics and driving forces of mechanochemical transformations. Furthermore, all ball milling reactions end with a steady state or milling equilibrium – represented by a specific phase composition and relative microstructure – that does not change as long as the milling conditions are maintained. The use of a standard sample is essential to determine the instrumental contribution to the X-ray powder diffraction (XRPD) peak broadening for time-resolved in situ (TRIS) monitoring of mechanochemical reactions under in operando conditions. Using TRIS-XRPD on a ball milling setup, coupled with low-energy synchrotron radiation, we investigated different data acquisition and analysis strategies on a silicon standard powder. The diffraction geometry and the microstructural evolution of the standard itself have been studied to model the instrumental contribution to XRPD peak broadening throughout the grinding activity. Previously proposed functions are here challenged and further developed. Importantly, we show that minor drifts of the jar position do not affect the instrumental resolution function significantly. We here report and discuss the results of such investigations and their application to TRIS-XRPD datasets of inorganic and organic ball mill grinding reactions.
KW - Mechanochemistry
KW - In situ diffraction
KW - Synchrotron radiation
KW - Sustainable chemisry
PY - 2022
U6 - https://doi.org/10.1039/d2fd00104g
SP - 1
EP - 17
PB - Royal Society of Chemistry
AN - OPUS4-55932
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rautenberg, Max
A1 - Bhattacharya, Biswajit
A1 - Das, Chayanika
A1 - Emmerling, Franziska
T1 - Mechanochemical Synthesis of Phosphonate-Based Proton Conducting Metal-Organic Frameworks
N2 - Water-stable metal−organic frameworks (MOFs) with proton-conducting behavior have attracted great attention as promising materials for proton-exchange membrane fuel cells. Herein, we report the mechanochemical gram-scale synthesis of three new mixed-ligand phosphonate-based MOFs, {Co(H2PhDPA)(4,4′-bipy)H2O)·2H2O}n (BAM-1), {Fe(H2PhDPA)(4,4′-bipy) (H2O)·2H2O}n (BAM-2), and {Cu(H2PhDPA)(dpe)2(H2O)2·2H2O}n (BAM-3) [where H2PhDPA = phenylene diphosphonate, 4,4′-bipy = 4,4′-bipyridine, and dpe = 1,2-di(4-pyridyl)ethylene]. Single-crystal X-ray diffraction measurements revealed that BAM-1 and BAM-2 are isostructural and possess a three-dimensional (3D) network structure comprising one-dimensional (1D) channels filled with guest water molecules. Instead, BAM-3 displays a 1D network structure extended into a 3D supramolecular structure through hydrogenbonding and π−π interactions. In all three structures, guest water molecules are interconnected with the uncoordinated acidic hydroxyl groups of the phosphonate moieties and coordinated water molecules by means of extended hydrogen-bonding interactions. BAM-1 and BAM-2 showed a gradual increase in proton conductivity with increasing temperature and reached 4.9 × 10−5 and 4.4 × 10−5 S cm−1 at 90 °C and 98% relative humidity (RH). The highest proton conductivity recorded for BAM-3 was 1.4 × 10−5 S cm−1 at 50 °C and 98% RH. Upon further heating, BAM-3 undergoes dehydration followed by a phase transition to another crystalline form which largely affects its performance. All compounds exhibited a proton hopping (Grotthuss model) mechanism, as suggested by their low activation energy.
KW - Mechanochemistry
KW - Metal-organic-frameworks
KW - Proton conductivity
PY - 2022
U6 - https://doi.org/10.1021/acs.inorgchem.2c01023
VL - 61
SP - 10801
EP - 10809
PB - ACS Publications
AN - OPUS4-55448
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ghazanfari, M. R.
A1 - Vittadello, L.
A1 - Al-Sabbagh, Dominik
A1 - Santhosh, A.
A1 - Frankcom, C.
A1 - Fuß, F.
A1 - von Randow, C. A.
A1 - Siemensmeyer, K.
A1 - Vrijmoed, J. C.
A1 - Emmerling, Franziska
A1 - Jerabek, P.
A1 - Irmlau, M.
A1 - Thiele, G.
T1 - Remarkable Infrared Nonlinear Optical, Dielectric, and Strong Diamagnetic Characteristics of Semiconducting K3[BiS3]
N2 - The ternary sulfido bismuthate K3[BiS3] is synthesized in quantitative yields. The material exhibits nonlinear optical properties with strong second harmonic generation properties at arbitrary wavelengths in the infrared spectral range and a notable laser-induced damage threshold of 5.22 GW cm−2 for pulsed laser radiation at a wavelength of 1040 nm, a pulse duration of 180 fs, and a repetition rate of 12.5 kHz. K3[BiS3] indicates semiconductivity with a direct optical band gap of 2.51 eV. Dielectric and impedance characterizations demonstrate κ values in the range of 6−13 at 1 kHz and a high electrical resistivity. A strong diamagnetic behavior with a susceptibility of −2.73 × 10−4 m3 kg−1 at room temperature is observed. These results suggest it is a promising nonlinear optical candidate for the infrared
region. The synergic physical characteristics of K3[BiS3] provide insight into the correlation of optical, electrical, and magnetic properties.
KW - Electrical properties
KW - Insulators
KW - Materials
KW - Nonlinear optics
KW - Quantum mechanics
PY - 2022
U6 - https://doi.org/10.1021/acs.jpclett.2c01689
VL - 13
IS - 30
SP - 6987
EP - 6993
PB - ACS Publications
AN - OPUS4-55456
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - Cocrystal polymorphs & Mechanochemistry - Mechanism & Kinetics
N2 - Mechanochemistry is an effective, environmentally benign, and facile method for the synthesis of new crystal forms. Different milling parameters are known to affect the mechanisms and rates of product formation: milling frequency, milling time, filling degree of the milling jar, ball diameter and vessel size, degree of milling ball filling, and material of jars. The increasing interest in mechanochemistry is contrasted by a limited mechanistic understanding of mechanochemical reactivity and selectivity. Control over ball milling transformations is needed before the transformative potential of mechanochemical processing can be realized. Different analytical methods and their combinations have been developed for the time-resolved in situ monitoring of mechanochemical transformations, including powder X-ray diffraction, X-ray absorption spectroscopy, NMR, Raman spectroscopy, and thermography. Here we will discuss our recent results investigating the formation of polymorphic cocrystals thereby elucidating the influence of milling parameters (solvent, temperature, time) and reaction sequences on the formation mechanism and kinetics. For the mechanochemical chlorination reaction of hydantoin normalizing the kinetic profiles to the volume of the milling ball showed clearly that milling reaction kinetics are conserved. Here physical kinetics dominate reaction rates in a ball-milling transformation. Attempting to interpret such kinetics in purely chemical terms risk misinterpreting the results. Our results indicate that time-resolved in situ investigations of milling reactions offer a new approach to tune and optimize mechanochemical processes.
T2 - 33th European Crrystallography Meeting
CY - Versailles, France
DA - 23.08.2022
KW - Mechanochemistry
KW - Cocrystals
KW - Kinetics
KW - Polymorphs
PY - 2022
AN - OPUS4-55586
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Lakshmipathi, M.
A1 - Emmerling, Franziska
A1 - Bhattacharya, Biswajit
A1 - Ghosh, S.
T1 - Structure-mechanical property correlation of a series of 4-(1-Napthylvinyl) pyridine based cocrystals
N2 - We obtained three 4-(1-Napthylvinyl) pyridine based cocrystals ( 1–3 ) and studied its structure mechan- ical property correlation which aimed towards various applications for photo switches, mechanical ac- tuators etc. Selection of coformer molecules is important in fine tuning mechanical property outcome of synthesized cocrystals. Amongst three cocrystals, cocrystal 1 is mechanically flexible and its mechani- cal property is attributed to underlying crystal packing features which is in line with existing elastically bendable crystals while other two cocrystals ( 2, 3 ) are brittle in nature. Hirshfeld analysis was carried out to illustrate structure-property correlation particularly in terms of number as well as types of non- covalent interactions in the lattice and further to corroborate the space of the molecules in the lattice.
KW - Cocrystals
KW - Mechanical properties
KW - Halogen bond interaction
KW - Structure-mechanical property correlation
PY - 2022
U6 - https://doi.org/10.1016/j.molstruc.2022.133670
SN - 0022-2860
VL - 1268
SP - 1
EP - 16
PB - Elsevier
CY - Amsterdam
AN - OPUS4-55547
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Thekkeppat, N. P.
A1 - Bhattacharya, Biswajit
A1 - Tothadi, S.
A1 - Ghosh, S.
T1 - Mechanically flexible crystals of styryl quinoline derivatives
N2 - Herein, we report three crystals of styryl quinoline derivatives. All these three crystals are mechanically flexible crystals, isostructural and also all of them comply with the common underlying features for elas- tic flexibility like absence of slip plane, criss-cross packing arrangement of neighbouring tapes, presence of weak and dispersive interactions such as halogen bonds, hydrogen bonds etc. The interactions facilitate easy movement of molecules under application of pressure thereby imparting elasticity. Further, the crys- tals were found to be blue light emitting making them promising candidates for optical waveguides. The optical properties were combined with flexibility by using crystal engineering approach towards achiev- ing various applications such as flexible OLEDs, optical waveguides, flexible optoelectronics etc.
KW - Mechanical flexibility
KW - Halogen bond
KW - Fluorescence
PY - 2022
U6 - https://doi.org/10.1016/j.molstruc.2022.133293
SN - 0022-2860
VL - 1265
SP - 1
EP - 7
PB - Elsevier
CY - Amsterdam
AN - OPUS4-55549
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - George, Janine
A1 - Petretto, G.
A1 - Naik, Aakash Ashok
A1 - Esters, M.
A1 - Jackson, A. J.
A1 - Nelson, R.
A1 - Dronskowski, R.
A1 - Rignanese, G.-M.
A1 - Hautier, G.
T1 - Cover profile for the article "Automated bonding analysis with crystal orbital Hamilton populuations"
N2 - Invited for this month’s cover are researchers from Bundesanstalt für Materialforschung und -prüfung (Federal Institute for Materials Research and Testing) in Germany, Friedrich Schiller University Jena, Université catholique de Louvain, University of Oregon, Science & Technology Facilities Council, RWTH Aachen University, Hoffmann Institute of Advanced Materials, and Dartmouth College. The cover picture shows a workflow for automatic bonding analysis with Python tools (green python). The bonding analysis itself is performed with the program LOBSTER (red lobster). The starting point is a crystal structure, and the results are automatic assessments of the bonding situation based on Crystal Orbital Hamilton Populations (COHP), including automatic plots and text outputs. Coordination environments and charges are also assessed. More information can be found in the Research Article by J. George, G. Hautier, and co-workers.
KW - Automation
KW - Chemical bonds
KW - High-throughput
PY - 2022
U6 - https://doi.org/10.1002/cplu.202200246
SN - 2192-6506
SP - 1
EP - 2
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-55557
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - Cocrystal polymorphs & Mechanochemistry - Mechanism & Kinetics
N2 - Mechanochemistry is an effective, environmentally benign, and facile method for the synthesis of new crystal forms. Different milling parameters are known to affect the mechanisms and rates of product formation: milling frequency, milling time, filling degree of the milling jar, ball diameter and vessel size, degree of milling ball filling, and material of jars. The increasing interest in mechanochemistry is contrasted by a limited mechanistic understanding of mechanochemical reactivity and selectivity. Control over ball milling transformations is needed before the transformative potential of mechanochemical processing can be realized. Different analytical methods and their combinations have been developed for the time-resolved in situ monitoring of mechanochemical transformations, including powder X-ray diffraction, X-ray absorption spectroscopy, NMR, Raman spectroscopy, and thermography. Here we will discuss our recent results investigating the formation of polymorphic cocrystals thereby elucidating the influence of milling parameters (solvent, temperature, time) and reaction sequences on the formation mechanism and kinetics. For the mechanochemical chlorination reaction of hydantoin normalizing the kinetic profiles to the volume of the milling ball showed clearly that milling reaction kinetics are conserved. Here physical kinetics dominate reaction rates in a ball-milling transformation. Attempting to interpret such kinetics in purely chemical terms risk misinterpreting the results. Our results indicate that time-resolved in situ investigations of milling reactions offer a new approach to tune and optimize mechanochemical processes.
T2 - 3rd CEFMC meeting
CY - Kashmir, India
DA - 31.08.2022
KW - Mechanochemistry
KW - Crystal Engeneering
PY - 2022
AN - OPUS4-55641
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Mit Hilfe künstlicher Intelligenz neue Materialien finden
N2 - Dieser Vortrag wurde im Rahmen einer Outreach-Veranstaltung für Schüler*innen gehalten (https://www.hansenberg.de/lernen/hansenberg-summit/summit-2022.html). Er beschreibt, wie wir an der BAM und an anderen Institutionen nach neuen Materialien suchen.
T2 - Hansenberg Summit
CY - Geisenheim, Germany
DA - 09.07.2022
KW - Materialdesign
KW - Materialinformatik
PY - 2022
AN - OPUS4-55408
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Automated bonding analysis based on crystal orbital Hamilton populations
N2 - We created a workflow that fully automates bonding analysis using Crystal Orbital Hamilton Populations, which are bond-weighted densities of states. This enables understanding of crystalline material properties based on chemical bonding information. To facilitate data analysis and machine-learning research, our tools include automatic plots, automated text output, and output in machine-readable format.
T2 - Sommersymposium des Fördervereins Chemieolympiade
CY - Online meeting
DA - 25.06.2022
KW - Bonding Analysis
KW - Automation
KW - DFT
PY - 2022
AN - OPUS4-55409
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Data-Driven Chemical Understanding
N2 - This talk presents my research on data-driven chemical understanding to graduate students in chemistry at the Graduate School Chemistry in Paris.
T2 - Workshop : Practical applications of Machine Learning in chemistry: perspectives and pitfalls
CY - Paris, France
DA - 13.07.2022
KW - Chemical Understanding
KW - Automation
KW - Bonding Analysis
PY - 2022
UR - https://gs-chem13.sciencesconf.org/
AN - OPUS4-55410
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Arnold, M.
A1 - Katzmann, J.
A1 - Naik, Aakash Ashok
A1 - Görne, A. L.
A1 - Härtling, Thomas
A1 - George, Janine
A1 - Schuster, C.
T1 - Investigations on electron beam irradiated rare-earth doped SrF2 for application as low fading dosimeter material: Evidence for and DFT simulation of a radiation-induced phase
N2 - A recent approach to measure electron radiation doses in the kGy range is the use of phosphors with an irradiation dose-dependent luminescence decay time. However, the applicability of the previously investigated material NaYF4:Yb3+,Er3+ is limited as it shows pronounced fading. Therefore, in this work, a modified SrF2 synthesis is presented that results in SrF2 nanoparticles codoped with Yb and either Er, Hm, or Tm. To assess their suitability as dosimeter material, dose response, as well as its degree of fading over 50 up to 140 days after irradiation were measured. Fading rates as small as 5% in SrF2:Er,Yb and 4% in SrF2:Ho,Yb were derived, which are comparable to established dosimeter materials. A combination of spectroscopy, diffraction and DFT calculations was used to elucidate the effect of irradiation, pointing towards the formation of a secondary phase of Yb2+ that we predict could be Yb2OF2. This irreversible formation of a secondary phase is considered to be the explanation for the low fading behavior in SrF2-based phosphors compared to NaYF4:Yb, Er, a highly attractive feature for electron beam dosimetry.
KW - DFT
KW - Structure prediction
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-554115
SN - 2050-7526
VL - 10
IS - 32
SP - 11579
EP - 11587
PB - RSC
CY - London
AN - OPUS4-55411
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - Mechanochemical formation of multicomponent crystal systems: Mechanism & Kinetics
N2 - Mechanochemistry is an effective, environmentally benign, and facile method for the synthesis of new multicomponent crystal systems. Different milling parameters are known to affect the mechanisms and rates of product formation: milling frequency, milling time, filling degree of the milling jar, ball diameter and vessel size, degree of milling ball filling, and material of jars. The increasing interest in mechanochemistry is contrasted by a limited mechanistic understanding of the mechanochemical reactivity and selectivity.
Different analytical methods and their combinations have been developed for the time resolved in situ monitoring of mechanochemical transformations, including powder X-ray diffraction, X-ray adsorption spectroscopy, NMR, Raman spectroscopy, and thermography.
Here we will discuss our recent results investigating the formation of (poly-morphic) cocrystals, metal-organic compounds, and salts, thereby elucidating the influence of milling parameters and reaction sequences on the formation mechanism and kinetics. For the mechanochemical chlorination reaction of hydantoin normalizing the kinetic profiles to the volume of the milling ball showed clearly that milling reaction kinetics are conserved. Here physical kinetics dominate reaction rates in a ball-milling transformation. Attempting to interpret such kinetics in purely chemical terms risk misinterpreting the results.
Our results indicate that time-resolved in situ investigation of milling reactions offer a new approach to tune and optimize mechanochemical processes.
T2 - 25th International Conference on the Chemistry of the Organic Solid State (ICCOSS XXV)
CY - Ohrid, Macedonia
DA - 03.07.2022
KW - Mechanochemistry
KW - In situ real-time monitoring
KW - Crystal Engineering
PY - 2022
AN - OPUS4-55413
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - Mechanochemical formation of multicomponent crystals systems
N2 - Mechanochemistry is an effective, environmentally benign, and facile method for the synthesis of new multicomponent crystal systems. Different milling parameters are known to affect the mechanisms and rates of product formation: milling frequency, milling time, filling degree of the milling jar, ball diameter and vessel size, degree of milling ball filling, and material of jars. The increasing interest in mechanochemistry is contrasted by a limited mechanistic understanding of mechanochemical reactivity and selectivity.
Different analytical methods and their combinations have been developed for the time-resolved in situ monitoring of mechanochemical transformations, including powder X-ray diffraction, X-ray absorption spectroscopy, NMR, Raman spectroscopy, and thermography.
Here we will discuss our recent results investigating the formation of (polymorphic) cocrystals, metal-organic compounds, and salts, thereby elucidating the influence of milling parameters and reaction sequences on the formation mechanism and kinetics. Our results indicate that time-resolved in situ investigations of milling reactions offer a new approach to tune and optimize mechanochemical processes.
T2 - 5ECQUL Forging Bonds
CY - Lisbon, Portugal
DA - 12.07.2022
KW - Mechanochemistry
KW - In situ real-time monitoring
KW - N-Chlorination
PY - 2022
AN - OPUS4-55414
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - Shaken not stirred: enhancing the flavor of mechanochemistry
N2 - compounds and cocrystals. The ever-increasing interest in this method is contrasted by a limited mechanistic understanding of the mechanochemical reactivity and selectivity. Different milling parameters are known to affect the mechanisms and rates of product formation: milling frequency, milling time, filling degree of the milling jar, ball diameter and vessel size, degree of milling ball filling, and material of jars. Time-resolved in situ investigations of milling reactions (Figure 1) provide direct insights into the underlying mechanisms. We recently introduced different setups enabling in situ investigation of mechanochemical reactions using synchrotron XRD and XAS combined with Raman spectroscopy and thermography. The presented setup allows the detection of crystalline, amorphous, eutectic, and liquid intermediates. Furthermore, the chemical composition of the reaction mixture was found to be directly correlated with changes in the temperature profile of the reaction. The resulting deeper kinetic and thermodynamic understanding of milling processes is the key to future optimization of mechanochemical syntheses. In this contribution, we will discuss our recent results investigating the formation of (polymorphic) cocrystals and coordination polymers. Our results indicate that time-resolved in situ investigations of mechanochemical processes are key for tuning and optimizing mechanochemical syntheses allowing to unleash the potential of mechanochemistry for a green materials design.
T2 - 2nd National Crystallographic Meeting Lisbon, Portugal
CY - Lisbon, Portugal
DA - 15.07.2022
KW - Mechanochemistry
KW - In situ real-time monitoring
KW - Crystal
PY - 2022
AN - OPUS4-55415
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - George, Janine
A1 - Naik, Aakash Ashok
T1 - DFT raw data for "Investigations on electron beam irradiated rare-earth doped SrF2 for application as low fading dosimeter material: Evidence for and DFT simulation of a radiation-induced phase"
N2 - DFT raw data for the publication https://doi.org/10.1039/D2TC01773C
It includes all predicted structures, the structure optimizations and the phonon computations in VASP format. Phonon computations were performed with the finite displacement method.
KW - DFT
KW - Phonons
KW - Structure prediction
PY - 2022
U6 - https://doi.org/10.5281/zenodo.5942729
PB - Zenodo
CY - Geneva
AN - OPUS4-55417
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - Mechanochemical formation of multicomponent crystal systems: Mechanism & Kinetics
N2 - Mechanochemistry is an effective, environmentally benign, and facile method for the synthesis of new multicomponent crystal systems. Different milling parameters are known to affect the mechanisms and rates of product formation: milling frequency, milling time, filling degree of the milling jar, ball diameter and vessel size, degree of milling ball filling, and material of jars. The increasing interest in mechanochemistry is contrasted by a limited mechanistic understanding of the mechanochemical reactivity and selectivity. Different analytical methods and their combinations have been developed for the time resolved in situ monitoring of mechanochemical transformations, including powder X-ray diffraction, X-ray adsorption spectroscopy, NMR, Raman spectroscopy, and thermography.1 Here we will discuss our recent results investigating the formation of (polymorphic) cocrystals2–3 and metal-organic frameworks,4 thereby elucidating the influence of milling parameters and reaction sequences on the formation mechanism and kinetics. For the mechanochemical chlorination reaction of hydantoin normalizing the kinetic profiles to the volume of the milling ball showed clearly that milling reaction kinetics are conserved.6 Here physical kinetics dominate reaction rates in a ball-milling transformation. Attempting to interpret such kinetics in purely chemical terms risk misinterpreting the results. Our results indicate that time-resolved in situ investigation of milling reactions offer a new approach to tune and optimize mechanochemical processes.
T2 - 10th International conference on Mechanochemistry and Mechanical Alloying
CY - Cagliari, Italy
DA - 06.06.2022
KW - Mechanochemistry
KW - In situ real-time monitoring
KW - Cocrystal
PY - 2022
AN - OPUS4-55421
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dubey, A.
A1 - Hon Keat, C.
A1 - Shvartsman, V.
A1 - Yusenko, Kirill
A1 - Escobar, M.
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Hagemann, U.
A1 - Kovalenko, S.
A1 - Stächler, J.
A1 - Lupascu, D.
T1 - Mono-, Di-, and Tri-valent Cation Doped BiFe0.95Mn0.05O3 Nanoparticles: Ferroelectric Photocatalysts
N2 - The ferroelectricity of multivalent co-doped Bismuth ferrite (BiFeO3; BFO) nanoparticles (NPs) is revealed and utilized for light photocatalysis exploiting their narrow electronic band gap. The photocatalytic activity of ferroelectric photocatalysts BiFe0.95Mn0.05O3 (BFM) NPs and mono-, di-, or tri-valent cations (Ag+, Ca2+, Dy3+; MDT) co-incorporated BFM NPs are studied under ultrasonication and in acidic conditions. We find that such doping enhances the photocatalytic activity of the ferroelectric NPs approximately three times. The correlation of the photocatalytic activity with structural, optical, and electrical properties of the doped NPs is established. The increase of spontaneous polarization by the mono- and tri-valent doping is one of the major factors in enhancing the photocatalytic performance along with other factors such as stronger light absorption in the visible range, low recombination rate of charge carriers and larger surface area of NPs. A-site doping of BFO NPs by divalent elements suppresses the polarization, whereas trivalent (Dy3+) and monovalent (Ag+) cations provide an increase of polarization. The depolarization field in these single domain NPs acts as a driving force to mitigate recombination of the photoinduced charge carriers.
KW - Piezoresponse
KW - Bismuth Ferrite
KW - Nanoparticles
KW - Photocatalysis
KW - Ferroelectric
KW - Polarization
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-557230
SN - 1616-301X
SP - 1
EP - 16
PB - Wiley
AN - OPUS4-55723
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rautenberg, Max
A1 - Bhattacharya, Biswajit
A1 - Witt, Julia
A1 - Jain, Mohit
A1 - Emmerling, Franziska
T1 - In situ time-resolved monitoring of mixed-ligand metal–organic framework mechanosynthesis
N2 - The mechanism of mixed-ligand metal–organic framework (MOF) formation, and the possible role of intermediate single-ligand metal complexes during mechanosynthesis, have not been explored yet. For the first time, we report here in situ real-time monitoring of the mechanochemical formation mechanism of mixed-ligand MOFs. Our results show that binary phases can act as intermediates or competing products in one-pot and stepwise synthesis.
KW - Mechanochemistry
KW - Metal-organic-frameworks
KW - In situ X-ray diffraction
KW - Mixed-ligand MOFs
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-558167
SP - 1
EP - 4
PB - Royal Society of Chemistry
AN - OPUS4-55816
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pakrashy, S.
A1 - Mandal, P. K.
A1 - Goswami, J. N.
A1 - Dey, S. K.
A1 - Choudhury, S. M.
A1 - Bhattacharya, Biswajit
A1 - Emmerling, Franziska
A1 - Alasmary, F. A.
A1 - Dolai, M.
T1 - Bioinformatics and Network Pharmacology of the First Crystal Structured Clerodin: Anticancer and Antioxidant Potential against Human Breast Carcinoma Cell
N2 - Clerodin was isolated from the medicinal plant Clerodendrum infortunatum, and CSD search showed the first crystal structure of clerodin by a single-crystal X-ray diffraction study. We checked its binding potential with target proteins by docking and conducted network pharmacology analysis, ADMET analysis, in silico pathway analysis, normal mode analysis (NMA), and cytotoxic activity studies to evaluate clerodin as a potential anticancer agent. The cell viability studies of clerodin on the human breast carcinoma cell line (MCF-7) showed toxicity on MCF-7 cells but no toxicity toward normal human lymphocyte cells (HLCs). The anticancer mechanism of clerodin was validated by its enhanced capacity to produce intracellular reactive oxygen species (ROS) and to lower the reduced glutathione content in MCF-7 cells.
KW - Anticancer
KW - Clerodin
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-567600
SN - 2470-1343
VL - 7
IS - 51
SP - 48572
EP - 48582
PB - ACS Publ.
CY - Washington, DC
AN - OPUS4-56760
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Naik, Aakash Ashok
A1 - George, Janine
T1 - Building quantum chemical orbital based bonding descriptor database
N2 - Motivation, methodology and and results of our quantum chemical bonding descriptors database presented in form of a Poster
T2 - RSC Twitter Conference 2023
CY - Online meeting
DA - 28.02.2023
KW - Bonding analysis
KW - Automation
KW - Materials Informatics
KW - Computational Chemistry
KW - Database
PY - 2023
UR - https://twitter.com/NaikAak/status/1630400167080869893
UR - https://twitter.com/NaikAak/status/1630540436434558977
AN - OPUS4-57101
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Bertin, Annabelle
T1 - Building macromolecular mimetics of cell constituents
N2 - One of the holy grails in chemistry is to reconstruct some of life’s functions with synthetic materials. In this contribution, we demonstrate that “simple” macromolecular architectures such as dendritic amphiphiles, Janus dendrimers, thermoresponsive and hybrid organic-inorganic (co)polymers enable to mimic some of the functions of proteins for biomineralization, natural bactericides, biological membranes or the stimuli-responsive cytoskeleton.
T2 - Makromolekulares Kolloquium Freiburg 2018
CY - Freiburg in Breisgau, Germany
DA - 21.02.2018
KW - Thermoresponsive polymers
KW - Cytoskeleton mimic
PY - 2018
AN - OPUS4-44296
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Bertin, Annabelle
A1 - Asadujjaman, Asad
T1 - Upper critical solution temperature (UCST)-type thermoresponsive polymers from hydrogen-bonding monomers
N2 - UCST-type thermoresponsive polymers (i.e. that phase separate from solution upon cooling) present a tremendous potential not only in aqueous media where they can be used in drug delivery, diagnostic and microfluidic applications, but also in water/alcohol mixtures, where they can be used for instance in sensing systems for alcohol-soluble drugs. However, only a few thermoresponsive polymers have been reported that present an UCST in a relevant temperature range and “green” solvents such as water or ethanol.
In this context, acrylamide-based monomers can be very useful building blocks for designing novel non-ionic UCST-type polymers because of their hydrophilic nature (with the appropriate side chain) and propensity to form hydrogen bonds. We will present our latest results on the UCST-type thermoresponsive behaviour of acrylamide- and 2,6-diaminopyridine-based homopolymers and copolymers in water or water/alcohol mixtures, and give some insights about the rational design of UCST polymers relying on H-bonding.
T2 - Invited talk (Dr. Jean-Francois Lutz) Institut Charles Sadron
CY - Strasbourg, France
DA - 26.01.2018
KW - Thermoresponsive polymer
KW - UCST-type polymer
KW - H bonds
KW - Diaminopyridine
KW - Acrylamide
PY - 2018
AN - OPUS4-44001
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Asadujjaman, Asad
A1 - Espinosa de Oliveira, T.
A1 - Mukherji, D.
A1 - Bertin, Annabelle
T1 - Polyacrylamide ‘‘revisited’’: UCST-type reversible thermoresponsive properties in aqueous alcoholic solutions
N2 - Combining experiments and all-atom molecular dynamics simulations, we study the conformational behavior of polyacrylamide (PAM) in aqueous alcohol mixtures over a wide range of temperatures. This study Shows that even when the microscopic interaction is dictated by hydrogen bonding, unlike its counterparts that present a lower critical solution temperature (LCST), PAM shows a counterintuitive tunable upper critical solution temperature (UCST)-type phase transition in water/alcohol mixtures that was not reported before. The Phase transition temperature was found to be tunable between 4 and 60 1C by the type and concentration of alcohol in the mixture as well as by the solution concentration and molecular weight of the polymer. In addition, molecular dynamics simulations confirmed a UCST-like behaviour of the PAM in aqueous alcoholic solutions.
Additionally, it was observed that the PAM is more swollen in pure alcohol solutions than in 80% alcoholic solutions due to y-like behaviour. Additionally, in the globular state, the size of the aggregates was found to increase with increasing solvent hydrophobicity and polymer concentration of the solutions. Above ist Phase transition temperature, PAM might be present as individual polymer chains in the coil state (r10 nm). As PAM is a widespread polymer in many biomedical applications (gel electrophoresis, etc.), this finding could be of high relevance for many more practical applications in high performance pharmaceuticals and/or sensors.
KW - Thermoresponsive polymer
KW - UCST-type polymer
KW - Polyacrylamide
KW - Water/alcohol mixtures
PY - 2018
U6 - https://doi.org/10.1039/c7sm02424j
SN - 1744-6848
SN - 1744-683X
VL - 14
IS - 8
SP - 1336
EP - 1343
PB - Royal Society of Chemistry
CY - London
AN - OPUS4-44002
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Woydt, Mathias
A1 - Wäsche, Rolf
A1 - Brandt, Guido
A1 - Ehrke, Roman
T1 - Tribology in hot steam - for waste heat recovery or for energy harvesting -
N2 - The wear rates of self-amted alumina couples show that friction as well as wear is largely determined by the above mentioned hydro-thermal conditions. The presence of water and ist amount available in the surrounding system either in liquid or in gaseous from plays a key role for friction and wear behavior and cabe benefical for the tribological profile of steam degradation resistant materials. Hot steam enhances the tribo-chemical formations of oxides and hydroxides on MgO-ZrO2, alumina and antimony impregnated carbon.
T2 - 21th International Colloquium Tribology
CY - Stuttgart/Ostfildern, Germany
DA - 09.01.2018
KW - Friction
KW - Alumina
KW - Hot steam
PY - 2018
AN - OPUS4-43895
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Czarnecki, Sebastian
A1 - Bertin, Annabelle
T1 - Hybrid silicon-based organic/inorganic block copolymers with sol-gel active moieties: Synthetic advances, self-assembly and applications in biomedicine and material science
N2 - Abstract: Hybrid silicon-based organic/inorganic (multi)block
copolymers are promising polymeric precursors to create
robust nano-objects and nanomaterials due to their sol–gel active moieties via self-assembly in solution or in bulk. Such nano-objects and nanomaterials have great potential in bio-medicine as nanocarriers or scaffolds for bone regeneration as well as in materials science as Pickering emulsifiers, pho-
tonic crystals or coatings/films with antibiofouling, antibac-
terial or water- and oil-repellent properties. Thus, this Review outlines recent synthetic efforts in the preparation of these hybrid inorganic/organic block copolymers, gives an
overview of their self-assembled structures and finally presents recent examples of their use in the biomedical field and
material science.
KW - Organic/inorganic block copolymer
KW - Robust nano objects
KW - Self-assembly
KW - Synthesis
KW - Biomedical application
KW - Material science
PY - 2018
U6 - https://doi.org/10.1002/chem.201705286
SN - 1521-3765
SN - 0947-6539
VL - 24
IS - 14
SP - 3354
EP - 3373
PB - WILEY-VCH Verlag GmbH & Co. KGaA
CY - Weinheim
AN - OPUS4-43953
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Topolniak, Ievgeniia
A1 - Hodoroaba, Vasile-Dan
A1 - Benemann, Sigrid
A1 - Pfeifer, Dietmar
A1 - Sturm, Heinz
T1 - Novel Boehmite-embedded organic/inorganic hybrid nanocomposite: cure behaviour, morphology and thermal properties
N2 - Hybrid materials have attracted growing interest during the last decade, particularly due to their extraordinary properties. Cycloalyphatic-epoxy oligosiloxane (CEO) resin was shown to be a good candidate as a barrier material for the encapsulation purposes. Incorporation of inorganic nanoparticles such as Boehmite (BA) into polymers was observed to modify their specific characteristics, in particular, thermal, thermo-oxidative and barrier ones. In this work, novel BA-embedded organic inorganic hybrid nanocomposite material was engineered by combining the advantageous properties of hybrid polymers and nanoparticle enhancement effect. Impacts of particles on the photocuring kinetics, degree of crosslinking and the resultant changes in the thermal properties of the cured films were investigated. CEO synthesis via condensation reaction was confirmed by 1H and 29Si NMR. The particle distribution within the films was verified by SEM including transmission mode coupled with EDX elemental analysis. Photocuring kinetics and thermal properties of the films were studied by in situ FTIR spectroscopy and DSC with TGA, respectively.
T2 - Deutschen Physikalischen Gesellschaft
CY - Berlin, Germany
DA - 11.03.2018
KW - Boehmite
KW - Nanocomposite
KW - Cycloalyphatic epoxy oligosiloxane
KW - CEO
PY - 2018
AN - OPUS4-44520
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Bertin, Annabelle
A1 - Asadujjaman, Asad
A1 - Ahmadi, Vahid
T1 - Upper critical solution temperature (UCST)-type thermoresponsive polymers from hydrogen-bonding monomers
N2 - UCST-type thermoresponsive polymers (i.e. that phase separate from solution upon cooling) present a tremendous potential not only in aqueous media where they can be used in drug delivery, diagnostic and microfluidic applications, but also in water/alcohol mixtures, where they can be used for instance in sensing systems for alcohol-soluble drugs. However, only a few thermoresponsive polymers have been reported that present an UCST in a relevant temperature range and “green” solvents such as water or ethanol.
In this context, acrylamide-based monomers can be very useful building blocks for designing novel non-ionic UCST-type polymers because of their hydrophilic nature (with the appropriate side chain) and propensity to form hydrogen bonds. We will present our latest results on the UCST-type thermoresponsive behaviour of acrylamide- and 2,6-diaminopyridine-based homopolymers and copolymers in water or water/alcohol mixtures, and give some insights about the rational design of UCST polymers relying on H-bonding.
T2 - Deutsche Physikalische Gesellschaft (DPG)-Frühjahrtagung 2018
CY - Berlin, Germany
DA - 11.03.2018
KW - Thermoresponsive polymer
KW - UCST-type polymer
KW - H bonds
KW - Diaminopyridine
KW - Acrylamide
PY - 2018
AN - OPUS4-44569
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Bertin, Annabelle
A1 - Asadujjaman, Asad
A1 - Ahmadi, Vahid
T1 - Upper critical solution temperature (UCST)-type thermoresponsive polymers from monomers with hydrogen-bonding interactions
N2 - UCST-type thermoresponsive polymers (i.e. that phase separate from solution upon cooling) present a tremendous potential not only in aqueous media where they can be used in drug delivery, diagnostic and microfluidic applications, but also in water/alcohol mixtures, where they can be used for instance in sensing systems for alcohol-soluble drugs. However, only a few thermoresponsive polymers have been reported that present an UCST in a relevant temperature range and “green” solvents such as water or ethanol.
In this context, acrylamide-based monomers can be very useful building blocks for designing novel non-ionic UCST-type polymers because of their hydrophilic nature (with the appropriate side chain) and propensity to form hydrogen bonds. We will present our latest results on the UCST-type thermoresponsive behaviour of acrylamide- and/or 2,6-diaminopyridine-based homopolymers and copolymers in water or water/alcohol mixtures, and give some insights about the rational design of UCST polymers relying on H-bonding.
T2 - Invited Talk (Prof. Christine Papadakis) Technische Universität München - Soft Matter Physics
CY - Munich, Germany
DA - 03.07.2018
KW - Thermoresponsive polymer
KW - UCST-type polymer
KW - H bonds
KW - Diaminopyridine
KW - Acrylamide
PY - 2018
AN - OPUS4-45423
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Bertin, Annabelle
T1 - Controlled self-assembly of Janus dendrimers via microfluidics
N2 - Vesicles self-assembled in water from natural and synthetic phospholipids (liposomes), amphiphilic block copolymers (polymersomes), and more recently amphiphilic Janus dendrimers (dendrimersomes) -5 as hollow soft structures in the nano size regime have attracted increasing interest as they can mimic primitive and contemporary biological membranes, and can be configured into biomimetic nanocapsules with application in nanomedicine such as gene, proteins and drug carriers or theranostics.
Compared to other amphiphilic structures, the molecular structure of Janus dendrimers can be precisely controlled: by using the vast range of tools from organic chemistry their size, architecture, density, generation as well as the number of end groups of the individual dendrons can be modified as desired.
Unfortunately, the controlled production of supramolecular aggregates made thereof is still a challenging task. Conventional batch-based techniques such as the solvent injection method or the film hydration method typically go along with a lack of control over self assembly/mixing and thus over size, morphology and size distribution of the vesicles.
The micromixer technology is a promising method for the controlled preparation of supramolecular assemblies as it allows control of mixing at microscale level. In addition, such microfluidic systems benefit from a high mixing efficiency, a low mixing time as well as from a reproducible and continuous production of soft nanoparticles. Herein, we report on the microfluidic-controlled self-assembly of Janus dendrimers as dendrimersomes and the impact of the mixing parameters on the self-assembly process.
T2 - Invited talk Leibniz Institute of Polymer Research Dresden (IPF)
CY - Dresden, Germany
DA - 08.03.2018
KW - Vesicles
KW - Janus dendrimers
KW - Microfluidics
PY - 2018
AN - OPUS4-44441
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Bertin, Annabelle
T1 - Building macromolecular mimetics of cell constituents
N2 - One of the holy grails in chemistry is to reconstitute some of life’s functions with or within synthetic materials. In this contribution, we demonstrate that “simple” macromolecular architectures such as dendritic amphiphiles, Janus dendrimers, thermoresponsive and hybrid organic-inorganic (co)polymers enable to mimic some of the functions of proteins for biomineralization, natural bactericides, biological membranes or the stimuli-responsive cytoskeleton.
T2 - Chemiedozententagung 2018
CY - Jena, Germany
DA - 05.03.2018
KW - UCST-type polymers
KW - Bioinspiration
KW - Thermoresponsive polymers
PY - 2018
AN - OPUS4-44442
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Bertin, Annabelle
A1 - Taabache, Soraya
A1 - Bertin, Annabelle
T1 - Dendritic Amphiphiles as Macromolecular Mimetics of Cellular Constituents
N2 - One of the holy grails in chemistry is to reconstruct some of life’s functions within synthetic materials. In this contribution, we demonstrate that “simple” macromolecular architectures such as dendritic amphiphiles, Janus dendrimers, thermoresponsive and hybrid organic-inorganic (co)polymers enable to mimic some of the functions of proteins for biomineralization, natural bactericides, biological membranes or the stimuli-responsive cytoskeleton.
T2 - Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS) - Dpt. des Matériaux Organiques (DMO), invited talk by Prof. Laurent Douce
CY - Strasbourg, France
DA - 09.02.2018
KW - Dendritic amphiphile
KW - Antibacterial properties
KW - Vesicles
KW - Microfluidic
PY - 2018
AN - OPUS4-44146
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Bertin, Annabelle
A1 - Asadujjaman, Asad
A1 - Espinosa de Oliveira, T.
A1 - Mukherji, D.
T1 - Upper critical solution temperature (UCST)-type thermoresponsive polymers from monomers with hydrogen-bonding interactions
N2 - UCST-type thermoresponsive polymers (i.e. that phase separate from solution upon cooling) present a tremendous potential not only in aqueous media with applications in the field of drug delivery, diagnostic and microfluidic applications, but also in water/alcohol mixtures, where they can be used for instance in sensing systems for alcohol-soluble drugs. However, only a few thermoresponsive polymers have been reported that present an UCST in a relevant temperature range and “green” solvents such as water or ethanol.
In this context, acrylamide-based monomers can be very useful building blocks for designing novel non-ionic UCST-type polymers because of their hydrophilic nature (with the appropriate side chain) and propensity to form hydrogen bonds. We will present our latest results on the UCST-type thermoresponsive behaviour of acrylamide- and/or 2,6-diaminopyridine-based homopolymers and copolymers in water or water/alcohol mixtures, and give some insights about the rational design of UCST polymers relying on H-bonding.
T2 - 7. Jahrestreffen der Seniorexperten Chemie
CY - Weimar, Germany
DA - 02.05.2018
KW - Thermoresponsive polymer
KW - UCST-type polymer
KW - Polyacrylamide
KW - Water/alcohol mixtures
PY - 2018
AN - OPUS4-44845
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Bertin, Annabelle
A1 - Asadujjaman, A.
A1 - Ahmadi, V.
T1 - Upper Critical Solution Temperature (UCST)-type Thermoresponsive Polymers from Hydrogen-Bonding Monomers
N2 - UCST-type thermoresponsive polymers (i.e. that phase separate from solution upon cooling) present a tremendous potential not only in aqueous media where they can be used in drug delivery, diagnostic and microfluidic applications,but also in water/alcohol mixtures, where they can be used for instance in sensing systems for alcohol-soluble drugs. However, only a few thermoresponsive polymers have been reported that present an UCST in a relevant temperature range and “green” solvents such as water or Ethanol.
In this context, acrylamide-based monomers can be very useful building blocks for designing novel non-ionic UCST-type polymers because of their hydrophilic nature (with the appropriate side chain) and propensity to form hydrogen bonds. We will present our latest results on the UCST-type thermoresponsive behaviour of acrylamide- and/or 2,6-diaminopyridine-based homopolymers and copolymers in water or water/alcohol mixtures, and give some insights about the rational design of UCST polymers relying on H-bonding.
T2 - Bordeaux Polymer Conference BPC 2018
CY - Bodeaux, France
DA - 28.05.2018
KW - Acrylamide
KW - Thermoresponsive polymer
KW - UCST-type polymer
KW - H-bonds
KW - Diaminopyridine
PY - 2018
AN - OPUS4-45155
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - de Oliveira, P. F. M.
A1 - Torresi, R.
A1 - Emmerling, Franziska
A1 - Carmago, P.
T1 - Challenges and opportunities in the bottom-up mechanochemical synthesis of noble metal nanoparticles
N2 - Mechanochemistry is a promising alternative to solution-based protocols across the chemical sciences, enabling different types of chemistries in solvent-free and environmentally benign conditions. The use of mechanical energy to promote physical and chemical transformations has reached a high level of refinement, allowing for the design of sophisticated molecules and nanostructured materials. Among them, the synthesis of noble metal nanoparticles deserves special attention due to their catalytic applications. In this review, we discuss the recent progress on the development of mechanochemical strategies for the controlled synthesis of noble metal nanostructures. We start by covering the fundamentals of different preparation routes, namely top-down and bottom-up approaches. Next, we focus on the key examples of the mechanochemical synthesis of non-supported and supported metal nanoparticles as well as hybrid nanomaterials containing noble metals. In these examples, in addition to the principles and synthesis mechanisms, their performances in catalysis are discussed. Finally, a perspective of the field is given, where we discuss the opportunities for future work and the challenges of mechanochemical synthesis to produce well-defined noble metal nanoparticles.
KW - Mechanochemistry
KW - Nanoparticles
PY - 2020
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-512080
VL - 8
IS - 32
SP - 16114
AN - OPUS4-51208
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Waske, Anja
A1 - Funk, Alexander
A1 - Jaenisch, Gerd-Rüdiger
A1 - Zscherpel, Uwe
A1 - Grunwald, Marcel
A1 - Moosavi, Robabeh
A1 - Redmer, Bernhard
A1 - Nazarzadehmoafi, Maryam
T1 - X-ray non-destructive testing of materials and composites
N2 - Using magnetic materials for energy conversion as an example, this lecture shows how X-ray tomography investigations can contribute to structure elucidation in composites and solid samples. The components are tested non-destructively in order to characterize cracks, pores and other defects and their influence on the functional properties three-dimensionally and in good time in the life cycle of the material. If you combine microtomography with other methods of magnetic material characterization, you can make unique statements about the structure and the functional properties.
T2 - TU Chemnitz Vortrag
CY - Chemnitz, Germany
DA - 04.11.2019
KW - X-Ray Imaging
KW - Additive Manufacturing
KW - Materials Science
KW - Non-destructiv testing
PY - 2019
AN - OPUS4-50150
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Waske, Anja
A1 - Funk, Alexander
A1 - Moosavi, Robabeh
A1 - Redmer, Bernhard
A1 - Nazarzadehmoafi, Maryam
A1 - Jaenisch, Gerd-Rüdiger
A1 - Zscherpel, Uwe
T1 - X-ray non-destructive testing of materials and composites
N2 - Using magnetic materials for energy conversion as an example, this lecture shows how X-ray tomography investigations can contribute to structure elucidation in composites and solid samples. The components are tested non-destructively in order to characterize cracks, pores and other defects and their influence on the functional properties three-dimensionally and in good time in the life cycle of the material. If you combine microtomography with other methods of magnetic material characterization, you can make unique statements about the structure and the functional properties.
T2 - Dcms
CY - Stockholm, Sweden
DA - 28.08.2019
KW - X-Ray imaging
KW - Additive Manufacturing
KW - Magnetocoloric
KW - Material Science
KW - Non-destructive testing
PY - 2019
AN - OPUS4-50151
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Asadujjaman, Asad
A1 - Ahmadi, Vahid
A1 - Franc, Antoine Michel Claude
A1 - Bertin, Annabelle
T1 - 2,6-Diaminopyridine and Acrylamide-Based Copolymers with Upper Critical Solution Temperature-type Behavior in Aqueous Solution
N2 - A novel cop olyme r based on supramolecular motif2,6-diaminopyridin e and water-soluble acrylamide, poly[N-(6-ace tamidopyridin-2-yl) acrylamide-co-acrylamide], was synthe-size d via rev ersible addi tion–fragmentation chain transfer (RAFT)polymerization with various monomer compositions. The thermo-respon sive behavior of the copolymers was studied by turbidime-try and dynamic light scattering (DLS). The obtained copolymersshowed an upper critical solution temperature (UCST)-typ e phasetransition behavior in water and electrolyte solution. The phasetransition temperature was found to increase with decreasingam ount of acrylamide in the copolymer and increasing concentra-tion of the solution. Furth ermore, the phase transition temperatureva ried in aqueous solutions of electrolytes according to the naturean d concentration of the electrolyte in accordance with theHoffmeister series. A dramatic solvent isotope effect on thetransition temperature was o bserved in this study, as the transitiontemperature was almost 10–12C higher in D2OthaninH2Oatthesame concentration and acrylamide co mposition. The size of theaggregates below the transition temperature was larger in D2Ocompared to that in H2O that can be explained by deuterium iso-tope effect. The thermoresponsive behavior of the copolymers wasalso investigated in different cell medium and found to be exhibitedUCST-type phase transition behavior in different cell medium.Such behavior of the copo lyme rs can be useful in many a pplica-tions including biomedical, microfluidics, optical materials, and indrug delivery.
KW - 2,6-diaminopyridine
KW - Acrylamide
KW - Stimuli-responsive polymers
KW - Thermo-responsive polymers
KW - UCST polymers
PY - 2019
U6 - https://doi.org/10.1002/pola.29474
SN - 0887-624X
VL - 57
IS - 19
SP - 2064
EP - 2073
PB - Wiley
AN - OPUS4-49297
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Waske, Anja
A1 - Funk, Alexander
A1 - Jaenisch, Gerd-Rüdiger
A1 - Zscherpel, Uwe
A1 - Moosavi, Robabeh
A1 - Grunwald, Marcel
A1 - Redmer, Bernhard
A1 - Nazarzadehmoafie, Maryam
T1 - X-ray non-destructive testing of materials and composites
N2 - Functional materials for energy conversion are important technology drivers needed for the implementation of low carbon energy. Therefore, researchers commonly focus on improving the intrinsic properties of a functional material. However, for applications, the extrinsic properties are at least as important as the intrinsic ones. Consequently, it is important to investigate and understand the external and internal structure of semi-finished products and especially defect dependent properties. The extrinsic properties may change during application and the life cycle of the material as well as through processing and molding steps.
Our studies show how X-ray tomographic (XCT) investigations can contribute to structure investigations in composites and massive samples using the example of magnetic materials for energy conversion. The components are tested non-destructively in 3D in order to localize and characterize cracks, pores, inclusions as well as other defects and their influence on the functional properties and also “in-time” during the life cycle of the material. Exsitu and in-situ experiments performed with non-destructive XCT are predestinated to follow damaging mechanisms of materials under certain load conditions, atmospheres or liquids, e.g. went through several working cycles of a functional material. By combining microtomography with other methods of magnetic and classical material characterization, unique statements about the structure and the functional properties can be made.
From the applications point of view, sometimes complex, three-dimensional geometries are needed to fully exploit the functional properties of the materials, e.g. to ensure a high surface area for heat exchange. Since many functional materials are brittle and difficult to form, shaping is often a big challenge. In principle, additive manufacturing processes offer the possibility to produce complex, porous components from poorly formable alloys.
If all stages of additive manufacturing are accompanied by X-ray tomographic imaging, the process of finding the optimal parameters for material processing can be significantly accelerated.
Based on the quality control of the initial powder material used and also investigations of the shape and arrangement of defects within the molten structure and their relationship with the melting path scanning strategy, Xray tomography has proven to be an ideal tool for additive manufacturing, even for functional materials. Overall, tomographic methods are important tools for the development of functional materials to application maturity.
T2 - Physikalisches Kolloquium TU Chemnitz
CY - Chemnitz, Germany
DA - 04.12.2019
KW - Non-destructuve testing
KW - X-ray imaging
KW - Additive manufacturing
KW - Materials science
PY - 2019
AN - OPUS4-50100
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Waske, Anja
A1 - Funk, Alexander
A1 - Jaenisch, Gerd-Rüdiger
A1 - Zscherpel, Uwe
A1 - Moosavi, Robabeh
A1 - Grunwald, Marcel
A1 - Hohendorf, Stefan
A1 - Onel, Yener
A1 - Redmer, Bernhard
T1 - X-ray Non-destructive testing of materials and composites
N2 - Functional materials for energy conversion are important technology drivers needed for the implementation of low carbon energy. Therefore, researchers commonly focus on improving the intrinsic properties of a functional material. However, for applications, the extrinsic properties are at least as important as the intrinsic ones. Consequently, it is important to investigate and understand the external and internal structure of semi-finished products and especially defect dependent properties. The extrinsic properties may change during application and the life cycle of the material as well as through processing and molding steps. Our studies show how X-ray tomographic (XCT) investigations can contribute to structure investigations in composites and massive samples using the example of magnetic materials for energy conversion.
T2 - Ruhr Universität Bochum - Seminar materials science and technology
CY - Online meeting
DA - 12.11.2020
KW - X-ray imaging
KW - Non-destructuve testing
KW - Functional materials
PY - 2020
AN - OPUS4-51905
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Almalla, A.
A1 - Hertwig, Andreas
A1 - Fischer, Daniel
A1 - Özcan Sandikcioglu, Özlem
A1 - Witt, Julia
T1 - Development of layer-by-layer assembled thin coatings on aluminium alloy AA2024-T3 for high resolution studies of local corrosion processes
N2 - The aim of this study is to develop nanometer-thin epoxy-based films on aluminium alloy AA2024-T3 as a model coating system for high resolution corrosion studies. Spin coating was used for the layer-by-layer (LbL) deposition of poly-(ethylenimine) (PEI) and poly([o-cresyl glycidyl ether]-co-formaldehyde) (CNER) bilayers. The film chemistry and the cross-linking process were characterized by means of Fourier-transform infrared spectroscopy (FTIR).
Ellipsometric data confirmed the linear increase of film thickness. The potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) results indicate the improvement of the film barrier properties with increasing film thickness. Mapping of the topography and the volta potential was performed by means of scanning Kelvin probe force microscopy (SKPFM).
The results indicate the presence of a homogeneous film structure, while the intermetallic phases can still be identified below the coating. The SKPFM Analysis confirmed that the model films are suitable for investigation of corrosion processes at the coating/metal interface.
KW - Spectroscopy
KW - Coatings
KW - Electrochemistry
KW - Microscopy
KW - Resins
PY - 2020
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-514627
SN - 0021-8995
VL - 137
IS - 48
SP - e49826-1
EP - e49826-9
PB - Wiley
CY - New York, NY
AN - OPUS4-51462
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Waske, Anja
T1 - Ethics in research for PhD students
N2 - The talk gives a short overview and explains basic principles of research ethics for PhD students. We examine the most important principles in the codes of conduct for good scientific practice on EU and national level. Based on these general rules, we give some hands-on practical tips for daily scientific work and discuss in detail one of the fields most susceptible to conflict, the topic of authorship in scientific publications.
T2 - Kick-off meeting ITN USES2
CY - Online meeting
DA - 09.11.2023
KW - Research ethics
KW - PhD training
PY - 2023
AN - OPUS4-58783
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Waske, Anja
A1 - Fähler, Sebastian
A1 - Fähler, Sebastian
T1 - Thermomagnetic generators with magnetocaloric materials for harvesting low grade waste heat
N2 - To date, there are very few technologies available for the conversion of low-temperature waste heat into electricity. Thermomagnetic generators are one approach proposed more than a century ago. Such devices are based on a cyclic change of magnetization with temperature. This switches a magnetic flux and, according to Faraday’s law, induces a voltage.
Here we give an overview on our research, covering both materials and systems. We demonstrate that guiding the magnetic flux with an appropriate topology of the magnetic circuit improves the performance of thermomagnetic generators by orders of magnitude. Through a combination of experiments and simulations, we show that a pretzel-like topology results in a sign reversal of the magnetic flux. This avoids the drawbacks of previous designs, namely, magnetic stray fields, hysteresis and complex geometries of the thermomagnetic material.
Though magnetocaloric materials had been the first choice also for thermomagnetic generators, they require some different properties, which we illustrate with Ashby plots for materials selection. Experimentally we compare La-Fe-Co-Si and Gd plates in the same thermomagnetic generator. Furthermore, we discuss corrosion and deterioration under cyclic use is a severe problem occurring during operation. To amend this, composite plates using polymer as a matrix have been suggested previously.
T2 - Dresden Days of Magnetocalorics
CY - Dresden, Germany
DA - 13.11.2023
KW - Thermomagnetic material
KW - Waste heat recovery
KW - Generator
PY - 2023
AN - OPUS4-58865
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Scheurrell, Kerstin
A1 - B. Martins, Inês C.
A1 - Murray, Claire
A1 - Emmerling, Franziska
T1 - Exploring the role of solvent polarity in mechanochemical Knoevenagel condensation: in situ investigation and isolation of reaction intermediates
N2 - Mechanochemistry has proven to be a highly effective method for the synthesis of organic compounds. We studied the kinetics of the catalyst-free Knoevenagel reaction between 4-nitrobenzaldehyde and malononitrile, activated and driven by ball milling. The reaction was investigated in the absence of solvents (neat grinding) and in the presence of solvents with different polarities (liquid-assisted grinding). The reaction was monitored using time-resolved in situ Raman spectroscopy and powder X-ray diffraction (PXRD). Our results indicate a direct relationship between solvent polarity and reaction kinetics, with higher solvent polarity leading to faster product (2-(4-nitrobenzylidone)malononitrile) formation. For the first time, we were able to isolate and determine the structure of an intermediate 2-(hydroxy(4-nitrophenyl)methyl)malononitrile based on PXRD data.
KW - Physical and Theoretical Chemistry
KW - General Physics and Astronomy
PY - 2023
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-588071
SN - 1463-9076
VL - 25
IS - 35
SP - 23637
EP - 23644
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-58807
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pérez Blanes, H.
A1 - Ghiasi, Pouria
A1 - Sandkühler, J.
A1 - Yesilcicek, Yasemin
A1 - Pentzien, Simone
A1 - Conradi, Andrea
A1 - Prinz, Carsten
A1 - Al-Sabbagh, Dominik
A1 - Thünemann, Andreas
A1 - Özcan Sandikcioglu, Özlem
A1 - Witt, Julia
T1 - High CO2 reduction activity on AlCrCoCuFeNi multi-principal element alloy nanoparticle electrocatalysts prepared by means of pulsed laser ablation
N2 - Noble metal-free nanoparticles (NPs) based on multi-principal element alloys (MPEAs) were synthesized using a one-step pulsed laser ablation in liquids (PLALs) method for the electrochemical reduction of CO2. Laser ablation was performed in pure water or poly-(diallyldimethylammonium chloride) (PDADMAC)-containing an aqueous solution of Al8Cr17Co17Cu8Fe17Ni33 MPEA targets. Transmission electron microscopy (TEM) measurements combined with energy dispersive X-ray (EDX) mapping were used to characterize the structure and composition of the laser-generated MPEA nanoparticles (MPEA-NPs). These results confirmed the presence of a characteristic elemental distribution of a core-shell phase structure as the predominant NP species. The electrocatalytic performance of the laser-generated MPEA-NPs was characterized by linear sweep voltammetry (LSV) demonstrating an enhanced electrocatalytic CO2 activity for PDADMAC-stabilized NPs. The findings of these investigations indicate that MPEAs have great potential to replace conventional, expensive noble metal electrocatalysts.
KW - Metals and Alloys
KW - Surfaces
KW - Biomaterials
KW - Ceramics and Composites
KW - Coatings and Films
PY - 2023
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-588218
SN - 2238-7854
VL - 24
SP - 9434
EP - 9440
PB - Elsevier B.V.
AN - OPUS4-58821
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Manoharan, Deepak
A1 - Ahmad, Shamim
A1 - Tothadi, Srinu
A1 - Emmerling, Franziska
A1 - Bhattacharya, Biswajit
A1 - Ghosh, Soumyajit
T1 - Linker size dependent mechanical properties of di-imine based molecular crystals
N2 - We have demonstrated the ability to modify the mechanical flexibility of molecular crystals by modulating the length of intervening linker moieties while keeping the terminal shape synthons the same.
KW - Mechanically flexible molecular crystals
KW - Mechanical properties
KW - Crystal Engineering
PY - 2023
U6 - https://doi.org/10.1039/D3CE00928A
SN - 1466-8033
SP - 1
EP - 8
PB - RSC
CY - London
AN - OPUS4-58836
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Bhattacharya, Biswajit
A1 - Akhmetova, Irina
A1 - Rautenberg, Max
A1 - Emmerling, Franziska
T1 - Mechanochemical synthesis of phosphonate-based proton conducting metal organic frameworks and hydrogen-bonded metal phosphonates
N2 - Proton exchange membrane fuel cells (PEMFCs) are one of the most promising alternative green energy technologies that deliver high energy density without CO2 emissions. The proton conductivity of proton exchange membranes (PEM) contributes to the overall efficiency of a PEMFC. Materials being used as PEMs must exhibit high proton conductivity at the working conditions of the targeted PEMFC. To date, Nafion and Nafion-like polymers with acidic functionality are widely used as membrane materials due to their high proton conductivity in the range of 10-1 to 10-2 Scm-1 at higher relative humidity. However, these materials suffer from high costs, hazardous production process, and poor performance at high temperatures, limiting their versatility.
In this context, crystalline porous materials are recognized as promising proton conductors for the proton exchange membrane (PEM) in fuel cell technology, owing to their tunable framework structure. However, it is still challenging bulk synthesis for real-world applications of these materials. Herein, we present mechanochemical gram-scale synthesis of series of mixed ligand metal organic frameworks (MOFs) and metal hydrogen‐bonded organic frameworks (MHOFs) using phenylene diphosphonic acid and 1-hydroxyethylidene-1,1-diphosphonic acid with different bipyridyl type of ligands, respectively. In all cases, the existence of extensive hydrogen bonds with amphiprotic uncoordinated phosphonate hydroxyl and oxygen atoms, the frameworks exhibited high proton conductivity. The study demonstrates the potential of green mechanosynthesis for preparations of framework-based proton conducting materials in bulk scale for green energy generation.
T2 - 4th International Conference on Phosphonate Chemistry, Science and Technology, ICOPHOS-4
CY - Crete, Greece
DA - 02.10.2023
KW - Proton exchange membrane fuel cells
KW - Metal organic frameworks
KW - Proton conducting materials
PY - 2023
AN - OPUS4-58837
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Cakir, Cafer Tufan
A1 - Radtke, Martin
A1 - Haider, M. Bilal
A1 - Emmerling, Franziska
A1 - F. M. Oliveira, P.
A1 - Michalchuk, Adam A. L.
T1 - Dispersive x-ray absorption spectroscopy for time-resolved in situ monitoring of mechanochemical reactions
N2 - X-ray absorption spectroscopy (XAS) provides a unique, atom-specific tool to probe the electronic structure of solids. By surmounting long-held limitations of powder-based XAS using a dynamically averaged powder in a Resonant Acoustic Mixer (RAM), we demonstrate how time-resolved in situ (TRIS) XAS provides unprecedented detail of mechanochemical synthesis. The use of a custom-designed dispersive XAS (DXAS) setup allows us to increase the time resolution over existing fluorescence measurements from ∼15 min to 2 s for a complete absorption spectrum. Hence, we here establish TRIS-XAS as a viable method for studying mechanochemical reactions and sampling reaction kinetics. The generality of our approach is demonstrated through RAM-induced (i) bottom-up Au nanoparticle mechanosynthesis and (ii) the synthesis of a prototypical metal organic framework, ZIF-8. Moreover, we demonstrate that our approach also works with the addition of a stainless steel milling ball, opening the door to using TRIS-DXAS for following conventional ball milling reactions. We expect that our TRIS-DXAS approach will become an essential part of the mechanochemical tool box.
KW - In situ studies
KW - Dipsersive XAS
KW - Mechanochemistry
KW - Time-resolved
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-567659
SN - 1089-7690
VL - 157
IS - 21
SP - 1
EP - 12
PB - American Institute of Physics
CY - Melville, NY
AN - OPUS4-56765
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Pauw, Brian Richard
A1 - Laskina, Sofya
A1 - Naik, Aakash Ashok
A1 - Smales, Glen Jacob
A1 - George, Janine
T1 - “Ultima Ratio”: Multi-scale, high-resolution 3D-FFT scattering pattern simulations
N2 - This talk highlights a proof-of-concept that demonstrates the ability to calculate high-resolution Fourier transforms. These can be combined with multi-scale modeling to simulate scattering over a wide range, from small-angle scattering to XRD and PDF.
T2 - Shapespyer/MuSSIC launch workshop
CY - Didcot, UK
DA - 20.02.2023
KW - X-ray scattering
KW - Simulation
KW - Fourier Transform
KW - 3D
KW - High resolution
KW - Multi-scale
PY - 2023
AN - OPUS4-57031
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Ertural, Christina
A1 - George, Janine
T1 - Vibe Check via Machine Learning: Testing the Prototype
N2 - Vibrational properties play a key role in determining the stability and thermal conductivity behaviour of materials. The quasi- harmonic approximation gives insight into the phononic properties of a compound, but in the established way, i.e. density functional theory based methods, it takes many calculation steps and consumes a lot of resources to arrive at the desired results. Machine learning (ML) trained interatomic potentials (e.g. Gaussian approximation potential, GAP) pose an alternative to the traditional computation way of phonons. We develop a Python code based workflow which combines automation tools like atomate2 with ML to ease providing interactomic potentials for (quantum chemical) computations and databases.
T2 - #RSCPoster Twitter conference 2023
CY - Online meeting
DA - 28.02.2023
KW - Interatomic potentials
KW - Machine learning
KW - Phonons
KW - Workflow
PY - 2023
UR - https://twitter.com/cer5814012/status/1630547004462858240
AN - OPUS4-57059
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Data-driven chemical understanding with geometrical and quantum-chemical bonding analysis
N2 - Chemical bonding and coordination environments are crucial descriptors of material properties. They have previously been applied to creating chemical design guidelines and chemical heuristics. They are currently being used as features in machine learning more and more frequently. I will discuss implementations and algorithms (ChemEnv and LobsterEnv) for identifying these coordination environments based on geometrical characteristics and chemical bond quantum chemical analysis. I will demonstrate how these techniques helped in testing chemical heuristics like the Pauling rule and thereby improved our understanding of chemistry. I will also show how these tools can be used to create new design guidelines and a new understanding of chemistry. To use quantum-chemical bonding analysis on a large-scale and for machine-learning approaches, fully automatic workflows and analysis tools have been developed. After presenting the capabilities of these tools, I will also point out how these developments relate to the general trend towards automation in the field of density functional based materials science.
T2 - UniSysCat - Colloquium
CY - Berlin, Germany
DA - 08.02.2023
KW - Automation
KW - Chemical Bonds
KW - High-throughput
KW - Data Analysis
PY - 2023
UR - https://www.unisyscat.de/news-events/display?tx_news_pi1%5Baction%5D=detail&tx_news_pi1%5Bcontroller%5D=News&tx_news_pi1%5Bnews%5D=386&cHash=f95c8af783c08c2c6039440145a036bb
AN - OPUS4-57051
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Smekhova, A.
A1 - Kuzmin, A.
A1 - Siemensmeyer, K.
A1 - Luo, C.
A1 - Taylor, J.
A1 - Thakur, S.
A1 - Radu, F.
A1 - Weschke, E.
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Xiao, B.
A1 - Savan, A.
A1 - Yusenko, Kirill
A1 - Ludwig, A.
T1 - Local structure and magnetic properties of a nanocrystalline Mn-rich Cantor alloy thin film down to the atomic scale
N2 - The huge atomic heterogeneity of high-entropy materials along with a possibility to unravel the behavior of individual components at the atomic scale suggests a great promise in designing new compositionally complex systems with the desired multi-functionality. Herein, we apply multi-edge X-ray absorption spectroscopy (extended X-ray absorption fine structure (EXAFS), X-ray absorption near edge structure (XANES), and X-ray magnetic circular dichroism (XMCD)) to probe the structural, electronic, and magnetic properties of all individual constituents in the single-phase face-centered cubic (fcc)-structured nanocrystalline thin film of Cr20Mn26Fe18Co19Ni17 (at.%) high-entropy alloy on the local scale. The local crystallographic ordering and component-dependent lattice displacements were explored within the reverse Monte Carlo approach applied to EXAFS spectra collected at the K absorption edges of several constituents at room temperature. A homogeneous short-range fcc atomic environment around the absorbers of each type with very similar statistically averaged interatomic distances (2.54–2.55 Å) to their nearest-neighbors and enlarged structural relaxations of Cr atoms were revealed. XANES and XMCD spectra collected at the L2,3 absorption edges of all principal components at low temperature from the oxidized and in situ cleaned surfaces were used to probe the oxidation states, the changes in the electronic structure, and magnetic behavior of all constituents at the surface and in the sub-surface volume of the film. The spin and orbital magnetic moments of Fe, Co, and Ni components were quantitatively evaluated. The presence of magnetic phase transitions and the co-existence of different magnetic phases were uncovered by conventional magnetometry in a broad temperature range.
KW - Magnetism
KW - High-entropy alloys
KW - Reverse Monte Carlo (RMC)
KW - Element-specific spectroscopy
KW - Extended X-ray absorption fine structure (EXAFS),
KW - X-ray magnetic circular dichroism (XMCD),
PY - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-578254
SN - 1998-0124
SP - 5626
PB - Springer
AN - OPUS4-57825
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bhattacharya, Biswajit
A1 - Michalchuk, Adam A. L.
A1 - Silbernagl, Dorothee
A1 - Yasuda, N.
A1 - Feiler, Torvid
A1 - Sturm, Heinz
A1 - Emmerling, Franziska
T1 - An atomistic mechanism for elasto-plastic bending in molecular crystals
N2 - Mechanically flexible single crystals of molecular materials offer potential for a multitude of new directions in advanced materials design. Before the full potential of such materials can be exploited, insight into their mechanisms of action must be better understood. Such insight can be only obtained through synergistic use of advanced experimentation and simulation. We herein report the first detailed mechanistic study of elasto-plastic flexibility in a molecular solid. An atomistic origin for this mechanical behaviour is proposed through a combination of atomic force microscopy, μ-focus synchrotron X-ray diffraction, Raman spectroscopy, ab initio simulation, and computed elastic tensors. Our findings suggest that elastic and plastic bending are intimately linked and result from extensions of the same molecular deformations. The proposed mechanism bridges the gap between contested mechanisms, suggesting its applicability as a general mechanism for elastic and plastic bending in organic molecular crystals.
KW - Mechanical property
KW - Mechanical flexibility
KW - Organic crystal
PY - 2023
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-577722
SN - 2041-6520
VL - 14
IS - 13
SP - 3441
EP - 3450
PB - Royal Society of Chemisty (RSC)
CY - London/Cambridge
AN - OPUS4-57772
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Manoharan, D.
A1 - Megha, S. N.
A1 - Kiran, M. S. R. N.
A1 - Emmerling, Franziska
A1 - Bhattacharya, Biswajit
A1 - Ghosh, S.
T1 - Designing the Mechanical Plasticity of Benzylidene Indanones Based Molecular Crystals by Crystal Engineering
N2 - Mechanically flexible molecular crystals have important implications in flexible optoelectronics, optical waveguides, etc. We report a series of 2-benzylidene 1-indanone based plastic crystals. Moreover, we have shown how plasticity can be fine-tuned through controlling intermolecular interactions.
KW - Mechanical flexibility
KW - Organic crystal
KW - Mechanical property
PY - 2023
U6 - https://doi.org/10.1021/acs.cgd.2c01137
SN - 1528-7483
VL - 23
SP - 657
EP - 661
PB - ACS Publications
AN - OPUS4-57773
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rautenberg, Max
A1 - Akhmetova, Irina
A1 - Das, Chayanika
A1 - Bhattacharya, Biswajit
A1 - Emmerling, Franziska
T1 - Synthesis and In Situ Monitoring of Mechanochemical Preparation of Highly Proton Conductive Hydrogen-Bonded Metal Phosphonates
N2 - Crystalline porous materials are recognized as promising proton conductors for the proton exchange membrane (PEM) in fuel cell technology owing to their tunable framework structure. However, it is still a challenging bulk synthesis for real-world applications of these materials. Herein, we report the mechanochemical gram-scale synthesis of two isostructural metal hydrogen-bonded organic frameworks (MHOFs) of Co(II) and Ni(II) based on 1-hydroxyethylidenediphosphonic acid (HEDPH4) with 2,2′-bipyridine (2,2′-bipy): Co(HEDPH3)2(2,2′-bipy)·H2O (1) and Ni(HEDPH3)2(2,2′-bipy)·H2O (2). In situ monitoring of the mechanochemical synthesis using different synchrotron-based techniques revealed a one-step mechanism – the starting materials are directly converted to the product. With the existence of extensive hydrogen bonds with amphiprotic uncoordinated phosphonate hydroxyl and oxygen atoms, both frameworks exhibited proton conduction in the range of 10–4 S cm–1 at room temperature under humid conditions. This study demonstrates the potential of green mechanosynthesis for bulk material preparation of framework-based solid-state proton conductors.
KW - Mechanochemistry
KW - Proton conductivity
KW - Metal Organic Frameworks
PY - 2023
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-577777
VL - 8
IS - 19
SP - 16687
EP - 16693
PB - ACS Publications
AN - OPUS4-57777
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Amariamir, Sasan
A1 - Benner, Philipp
A1 - George, Janine
T1 - Prediction of materials synthesizability
N2 - In the pursuit of discovering materials with desirable properties, extending the available material libraries is crucial. High-throughput simulations have become an integral part in designing new materials in the past decades. However, there is no straightforward way of distinguishing synthesizable materials from all the proposed candidates. This project focuses on employing AI-driven methods to estimate synthesizability of materials.
Up to now, material scientists and engineers have relied on domain knowledge as well as empirical heuristics to guess the stability and synthesizability of molecules and crystals. The famous Pauling rules of crystal stability are an example of such heuristics. However, after the accelerating material discovery in all the years since Pauling, these rules now fail to account for the stability of most known crystals. A new predictive set of heuristics for crystal stability/synthesizability is unlikely to be uncovered by human perception, given the magnitude and dimensionality of crystallographic data. Hence, a data-driven approach should be proposed to find a predictive model or set of heuristics which differentiate synthesizable crystal structures from the rest. The main challenge of this research problem is the lack of a negative set for classification. Here, there are two classes of data: the positive class which contains synthesizable materials and the negative class which contains materials which are not synthesizable. While the data from the positive class is simply the data of crystals which have been experimentally synthesized, we do not have access to data points which are certainly unsynthesizable. Strictly speaking, if an attempt of synthesizing a crystal fails, it does not necessarily follow that the crystal is not synthesizable. Also, there is no database available which contains the intended crystal structures of unsuccessful synthesis attempts.
This project proposes a semi-supervised learning scheme to predict crystal synthesizability. The ML model is trained on experimental and theoretical crystal data. The initial featurization focuses on local environments which is inspired by the Pauling Rules. The experimental data points are downloaded through the Pymatgen API from the Materials Project database which contains relaxed structures recorded in Inorganic Crystal Structure Database – ICSD. The theoretical data is queried from select databases accessible through the Optimade project’s API.
T2 - MSE Congress 2022
CY - Darmstadt, Germany
DA - 27.09.2022
KW - Synthesizability
KW - PU Learning
KW - Cheminformatics
PY - 2022
AN - OPUS4-56731
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Getenet, M.
A1 - Otálora, F.
A1 - Emmerling, Franziska
A1 - Al-Sabbagh, Dominik
A1 - García-Ruiz, J. M.
T1 - Mineral precipitation and hydrochemical evolution through evaporitic processes in soda brines (East African Rift Valley)
N2 - Soda lakes of the East African Rift Valley are hyperalkaline, hypersaline lakes extremely enriched in Na+, K+, Cl−, CO32−, HCO3−, and SiO2. In this paper, we investigate the chemical evolution in these lakes and the production of chemical sediments by salt precipitation via evaporation. Water samples from tributary springs and three lakes (Magadi, Nasikie Engida and Natron) have been experimentally studied by in-situ X-ray diffraction during evaporation experiments to characterize the sequence of mineral precipitation. These data are complemented by ex-situ diffraction studies, chemical analyses and thermodynamic hydrochemical calculations producing detailed information on the activity of all solution species and the saturation state of all minerals potentially generated by the given composition. Major minerals precipitating from these samples are sodium carbonates/bicarbonates as well as halite. The CO3/HCO3 ratio, controlled by pH, is the main factor defining the Na‑carbonates precipitation sequence: in lake brines where CO3/HCO3 > 1, trona precipitates first whereas in hot springs, where CO3/HCO3 ≪ 1, nahcolite precipitates instead of trona, which forms later via partial dissolution of nahcolite. Precipitation of nahcolite is possible only at lower pH values (pCO2 higher than −2.7) explaining the distribution of trona and nahcolite in current lakes and the stratigraphic sequences. Later, during evaporation, thermonatrite precipitates, normally at the same time as halite, at a very high pH (>11.2) after significant depletion of HCO3− due to trona precipitation. The precipitation of these soluble minerals increases the pH of the brine and is the main factor contributing to the hyperalkaline and hypersaline character of the lakes. Villiaumite, sylvite, alkaline earth carbonates, fluorapatite and silica are also predicted to precipitate, but most of them have not been observed in evaporation experiments, either because of the small amount of precipitates produced, kinetic effects delaying the nucleation of some phases, or by biologically induced effects in the lake chemistry that are not considered in our calculations. Even in these cases, the chemical composition in the corresponding ions allows for discussion on their accumulation and the eventual precipitation of these phases. The coupling of in-situ and ex-situ experiments and geochemical modelling is key to understanding the hydrogeochemical and hydroclimatic conditions of soda lakes, evaporite settings, and potentially soda oceans of early Earth and other extraterrestrial bodies.
KW - Crystallization sequence
KW - Hydrochemical evolution
KW - Alkaline brines
KW - Sodium carbonate minerals
KW - Soda lakes
KW - Evaporite deposits
PY - 2023
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-568431
SN - 0009-2541
VL - 616
SP - 1
EP - 13
PB - Elsevier
CY - New York, NY
AN - OPUS4-56843
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Automated quantum-chemical bonding analysis with workflow tools
N2 - Bonds and local atomic environments are crucial descriptors of material properties. They have been used to create design rules and heuristics and as features in machine learning of materials properties. Implementations and algorithms (e.g., ChemEnv and LobsterEnv) for identifying local atomic environments based on geometrical characteristics and quantum-chemical bonding analysis are nowadays available. Fully automatic workflows and analysis tools have been developed to use quantum-chemical bonding analysis on a large scale. The lecture will demonstrate how our tools, that assess local atomic environments and perform automatic bonding analysis, help to develop new machine learning models and a new intuitive understanding of materials. Furthermore, other recent workflow contributions to the Materials Project software infrastructure (pymatgen, atomate2) related to phonons and machine-learning potentials will be discussed.
T2 - ADIS Workshop 2023
CY - Tegernsee, Germany
DA - 29.10.2023
KW - Automation
KW - Materials Properties
KW - DFT
KW - Workflows
KW - Machine Learning
KW - Thermodynamic Properties
PY - 2023
AN - OPUS4-58745
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Data-driven chemical understanding and machine learning of materials properties
N2 - Bonds and local atomic environments are crucial descriptors of material properties. They have been used to create design rules and heuristics for materials. More and more frequently, they are used as features in machine learning. Implementations and algorithms (e.g., ChemEnv and LobsterEnv) for identifying these local atomic environments based on geometrical characteristics and quantum-chemical bonding analysis are nowadays available. Fully automatic workflows and analysis tools have been developed to use quantum-chemical bonding analysis on a large scale and for machine-learning approaches. The latter relates to a general trend toward automation in density functional-based materials science. The lecture will demonstrate how our tools, that assess local atomic environments, helped to test and develop heuristics and design rules and an intuitive understanding of materials.
T2 - 16th International conference on materials chemistry (MC16)
CY - Dublin, Irland
DA - 03.07.2023
KW - Automation
KW - Bonding Analysis
KW - Materials Informatics
PY - 2023
AN - OPUS4-57876
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Ertural, Christina
A1 - Deringer, V. L.
A1 - George, Janine
T1 - Automation of machine learning driven interatomic potential generation for predicting vibrational properties
N2 - Investigating the phononic properties is beneficial for predicting low thermal conductivity thermoelectric materials.1–3 Employing density functional theory4 takes many calculation steps and consumes a lot of computational resources.5,6 Using machine learning driven interatomic potentials (MLIP, e.g., Gaussian approximation potential,8 GAP) opens up a faster route to phonons7 but in most cases, the potentials are specifically tailored for a certain compound. In this work, we automate the generation of such MLIPs in a Python code-based workflow, based on the automation tools atomate29 and pymatgen10 which combines the automatic DFT computations with the automated fitting of GAPs. Automation enables easier testing, benchmarking and validation.11 We aim to provide the workflow-generated potentials for storage in databases.
T2 - 16th International conference on materials chemistry (MC16)
CY - Dublin, Ireland
DA - 03.07.2023
KW - Interatomic potentials
KW - Machine learning
KW - Phonons
KW - Thermoelectrics
PY - 2023
AN - OPUS4-57932
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Ertural, Christina
T1 - Quantum chemical bonding analysis of functional materials using LOBSTER and automated workflows
N2 - A talk on how to use LOBSTER and automated workflows (supported by LobsterPy, atomate2 and more) to do quantum chemical bonding analysis for (functional) materials design.
T2 - Gastvortrag Inorganic Chemistry Laboratory, University of Oxford
CY - Oxford, UK
DA - 04.05.2023
KW - Chemical bonding
KW - Automated workflows
KW - Functional materials
PY - 2023
AN - OPUS4-57933
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Ertural, Christina
T1 - Workflows and automation (lecture/tutorial)
N2 - A lecture and tutorial on how to use workflows and automation methods for quantum chemical calculations.
T2 - Invited lecture
CY - Oxford, UK
DA - 28.04.2023
KW - Workflows
KW - Automation
KW - Quantum chemical bonding analysis
PY - 2023
AN - OPUS4-57934
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Bustamante, Joana
A1 - Naik, Aakash Ashok
A1 - Ertural, Christina
A1 - Ueltzen, Katharina
A1 - George, Janine
T1 - Thermodynamic and Thermoelectric Properties of the Canfieldite, (Ag8SnS6 ), in the Quasi-Harmonic Approximation
N2 - Argyrodite-type materials have lately sparked a lot of research interest due to their thermoelectric properties.One promising candidate is canfieldite (Ag8SnS6), which has a Pna21 orthorhombic crystal structure at room temperature (RT). Recently, a new low-temperature (LT) phase transition of canfieldite at 120K has been found. Here, we investigate structural, vibrational and thermodynamic properties of Ag8SnS6 at room- and low-temperature employing density functional theory (DFT) and lattice dynamics computations. Thermal properties calculations were based on the quasi-harmonic approximation (QHA) as implemented in phonopy. We achieve good agreement with experiments. Thermal properties such as the constant-pressure heat capacity (Cp) and thermal conductivity are very close to experimental measurements. Furthermore, we compared RT and LT Ag8SnS6 Grüneisen parameters with argyrodites analogues, Ag8XS6 (X = Sn, Si, Ge), to arrive at an improved
T2 - 16th International conference on materials chemistry (MC16)
CY - Dublin, Ireland
DA - 03.07.2023
KW - Thermoelectric materials
KW - DFT
KW - QHA
KW - Grüneisen parameter
PY - 2023
AN - OPUS4-57887
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Naik, Aakash Ashok
A1 - Ertural, Christina
A1 - Dhamrait, Nidal
A1 - Benner, Phillip
A1 - George, Janine
T1 - A Quantum-Chemical Bonding Database for Solid-State Materials
N2 - Understanding the chemistry and nature of individual chemical bonds is essential for materials design. Bonding analysis via the LOBSTER software package has provided valuable insights into the properties of materials for thermoelectric and catalysis applications. Thus, the data generated from
bonding analysis becomes an invaluable asset that could be utilized as features in large-scale data analysis and machine learning of material properties. However, no systematic studies exist that conducted high-throughput materials simulations to curate and validate bonding data obtained from LOBSTER. Here we present an approach to constructing such a large database consisting of quantum-chemical bonding information.
T2 - 16th International conference on materials chemistry (MC16)
CY - Dublin, Ireland
DA - 03.07.2023
KW - Bonding analysis
KW - Automation
KW - Materials Informatics
KW - Computational Chemistry
KW - Database
PY - 2023
AN - OPUS4-57889
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Yusenko, Kirill
T1 - Reaction of high-entropy alloys with hydrogen under extreme conditions
N2 - In the current study, we investigate an interaction under high-pressure high-temperature of single phase fcc-, hcp- and bcc-structured high-entropy alloys with hydrogen, carbon and nitrogen to obtain high-entropy hydrides, carbides and nitrides. Structural changes in high-entropy alloys upon compression and heating in the presence of these light elements are in the focus of our investigation. An easy route to high-entropy hydrides, carbides and nitrides will open new synthetic horizons in compositionally complex materials. Our study suggests that high-entropy alloys form high- entropy hydrides mainly with a composition close to M:H 1:1 ratio. Hydrides can be obtained under compression with hydrogen as a pressure compression medium or using hydrogen fluid as reactive agent.
T2 - Intermetallics 2023
CY - Bad Staffelstein, Germany
DA - 03.10.2023
KW - HEA
PY - 2023
AN - OPUS4-58555
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Somasundaram, S. K.
A1 - Buzanich, Ana
A1 - Emmerling, Franziska
A1 - Krishnan, S.
A1 - Senthilkumar, K.
A1 - Joseyphus, R.J.
T1 - New insights into pertinent Fe-complexes for the synthesis of iron via the instant polyol process
N2 - Chemically synthesized iron is in demand for biomedical applications due to its large saturation magnetization compared to iron oxides. The polyol process, suitable for obtaining Co and Ni particles and their alloys, is laborious in synthesizing Fe. The reaction yields iron oxides, and the reaction pathway remains unexplored. This study shows that a vicinal polyol, such as 1,2-propanediol, is suitable for obtaining Fe rather than 1,3-propanediol owing to the formation of a reducible Fe intermediate complex. X-ray absorption spectroscopy analysis reveals the ferric octahedral geometry and tetrahedral geometry in the ferrous state of the reaction intermediates in 1,2-propanediol and 1,3-propanediol, respectively. The final product obtained using a vicinal polyol is Fe with a γ-Fe2O3 shell, while the terminal polyol is favourable for Fe3O4. The distinct Fe–Fe and Fe–O bond lengths suggest the presence of a carboxylate group and a terminal alkoxide ligand in the intermediate of 1,2-propanediol. A large Fe–Fe bond distance suggests diiron complexes with bidentate carboxylate bridges. Prominent high-spin and low-spin states indicate the possibility of transition, which favors the reduction of iron ions in the reaction using 1,2-propanediol.
KW - XAS
KW - Nanoparticle
PY - 2023
U6 - https://doi.org/10.1039/D3CP01969A
SN - 1463-9076
VL - 25
IS - 33
SP - 21970
EP - 21980
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-58073
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Naik, Aakash
A1 - Ertural, Christina
A1 - Dhamrait, Nidal
A1 - Benner, Philipp
A1 - George, Janine
T1 - A Quantum-Chemical Bonding Database for Solid-State Materials
N2 - An in-depth insight into the chemistry and nature of the individual chemical bonds is essential for understanding materials. Bonding analysis is thus expected to provide important features for large-scale data analysis and machine learning of material properties. Such chemical bonding information can be computed using the LOBSTER software package, which post-processes modern density functional theory data by projecting the plane wave-based wave functions onto an atomic orbital basis. With the help of a fully automatic workflow, the VASP and LOBSTER software packages are used to generate the data. We then perform bonding analyses on 1520 compounds (insulators and semiconductors) and provide the results as a database. The projected densities of states and bonding indicators are benchmarked on standard density-functional theory computations and available heuristics, respectively. Lastly, we illustrate the predictive power of bonding descriptors by constructing a machine learning model for phononic properties, which shows an increase in prediction accuracies by 27% (mean absolute errors) compared to a benchmark model differing only by not relying on any quantum-chemical bonding features.
KW - Bonding Analysis
KW - DFT
KW - High-throughput
KW - Database
KW - Phonons
KW - Machine Learning
PY - 2023
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-582892
VL - 10
IS - 1
SP - 1
EP - 18
AN - OPUS4-58289
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - George, Janine
T1 - Handling of orbital-resolved "ICOHPLIST.lobster" files from the software Lobster in pymatgen
N2 - Python Materials Genomics (pymatgen) is a robust materials analysis code that defines classes for structures and molecules with support for many electronic structure codes. This open-source software package powers the Materials Project.
In this particular contribution, the handling of obital-resolved "ICOHPLIST.lobster" files from Lobster was implemented in the software package (github handle: @JaGeo).
KW - Bonding analysis
KW - Density functional theory
PY - 2023
UR - https://github.com/materialsproject/pymatgen/pull/2993
PB - Zenodo
CY - Geneva
AN - OPUS4-57569
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - George, Janine
T1 - JaGeo/Advanced_Jobflow_Tutorial: v.0.1.0
N2 - This tutorial is aimed at developers who would like to develop workflows with Jobflow. This could include contributions to atomate2 and quacc. Jobflow workflows can also be executed with Fireworks on Supercomputers.
This tutorial includes information on how to write a job for jobflows, how to connect jobs to a workflow including dynamic features and how to store job results in databases. The structure of the workflow is inspired by workflows that have been developed for atomate2 and quacc.
This tutorial is also connected to google collab so that you can execute the code via their services.
Please access the tutorial here: https://jageo.github.io/Advanced_Jobflow_Tutorial/intro.html
KW - Automation
KW - Computational Materials Science
PY - 2023
UR - https://jageo.github.io/Advanced_Jobflow_Tutorial/intro.html
U6 - https://doi.org/10.5281/zenodo.8004401
PB - Zenodo
CY - Geneva
AN - OPUS4-57588
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Manoharan, D.
A1 - Ahmad, S.
A1 - Emmerling, Franziska
A1 - Bhattacharya, Biswajit
A1 - Ghosh, S.
T1 - Stress and light sensitive dual-mechanical property of acylhydrazone crystal
N2 - Mechanically dual-responsive molecular crystals have gained ubstantial interest among researchers due to their significant applications in various fields. However, incorporation of disparate mechanical responses in the same crystalline material is still a challenging issue and is continuously being explored. Here, we report long acicular crystals derived from 4-bromobenzhydrazide and 9-anthraldehyde exhibit both stressinduced mechanical bending and blue-light induced photomechanical bending. Furthermore, the crystals show thermal back isomerization upon gradual heating. These two distinct mechanical responses in the crystalline phase have been studied and their structure–property correlation have been established.
KW - Light sensitive crystal
KW - Mechanical flexibility
KW - Organic crystal
PY - 2023
U6 - https://doi.org/10.1039/d3ce00296a
VL - 25
IS - 21
SP - 3237
EP - 3244
PB - Royal Society of Chemisty (RSC)
CY - London/Cambridge
AN - OPUS4-57593
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ghiringhelli, Luca M.
A1 - Baldauf, Carsten
A1 - Bereau, Tristan
A1 - Brockhauser, Sandor
A1 - Carbogno, Christian
A1 - Chamanara, Javad
A1 - Cozzini, Stefano
A1 - Curtarolo, Stefano
A1 - Draxl, Claudia
A1 - Dwaraknath, Shyam
A1 - Fekete, Ádám
A1 - Kermode, James
A1 - Koch, Christoph T.
A1 - Kühbach, Markus
A1 - Ladines, Alvin Noe
A1 - Lambrix, Patrick
A1 - Himmer, Maja-Olivia
A1 - Levchenko, Sergey V.
A1 - Oliveira, Micael
A1 - Michalchuk, Adam
A1 - Miller, Ronald E.
A1 - Onat, Berk
A1 - Pavone, Pasquale
A1 - Pizzi, Giovanni
A1 - Regler, Benjamin
A1 - Rignanese, Gian-Marco
A1 - Schaarschmidt, Jörg
A1 - Scheidgen, Markus
A1 - Schneidewind, Astrid
A1 - Sheveleva, Tatyana
A1 - Su, Chuanxun
A1 - Usvyat, Denis
A1 - Valsson, Omar
A1 - Wöll, Christof
A1 - Scheffler, Matthias
T1 - Shared metadata for data-centric materials science
N2 - The expansive production of data in materials science, their widespread sharing and repurposing requires educated support and stewardship. In order to ensure that this need helps rather than hinders scientific work, the implementation of the FAIR-data principles (Findable, Accessible, Interoperable, and Reusable) must not be too narrow. Besides, the wider materials-science community ought to agree on the strategies to tackle the challenges that are specific to its data, both from computations and experiments. In this paper, we present the result of the discussions held at the workshop on “Shared Metadata and Data Formats for Big-Data Driven Materials Science”. We start from an operative definition of metadata, and the features that a FAIR-compliant metadata schema should have. We will mainly focus on computational materials-science data and propose a constructive approach for the FAIRification of the (meta)data related to ground-state and excited-states calculations, potential-energy sampling, and generalized workflows. Finally, challenges with the FAIRification of experimental (meta)data and materials-science ontologies are presented together with an outlook of how to meet them.
KW - Library and Information Sciences
KW - Statistics, Probability and Uncertainty
KW - Computer Science Applications
KW - Education
KW - Information Systems
KW - Statistics and Probability
PY - 2023
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-584846
VL - 10
IS - 1
SP - 1
EP - 18
PB - Springer Science and Business Media LLC
AN - OPUS4-58484
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Okeke, Joseph
A1 - Widjaja, Martinus Putra
A1 - Waske, Anja
A1 - Markötter, Henning
A1 - Dayani, Shahabeddin
A1 - Eddah, Mustapha
A1 - Britton, M.
A1 - Kendrick, E.
A1 - Allan, P.
A1 - Alsofi, G.
A1 - Williams, E.
T1 - In situ and operando imaging, spectroscopy and tomography of batteries
N2 - The development of more powerful and more efficient lithium-ion batteries (LIBs) is a key area in battery research, aiming to support the ever-increasing demand for energy storage systems. To better understand the causes and mechanisms of degradation, and thus the diminishing cycling performance and lifetime often observed in LIBs, in operando techniques are essential, because battery chemistry can be monitored non-invasively, in real time. Moreover, there is increasing interest in developing new battery chemistries. Beyond LIBs, sodium ion batteries (NIBs) have gained increasing interest in recent years, as they are a promising candidate to complement LIBs, owing to their improved sustainability and lower cost, while still maintaining high energy density.[1] Initial phases of NIB commercialisation have occurred in the past year. However, for the widespread commercialisation of NIBs, there are still challenges that need to be overcome in developing optimized electrode materials and electrolytes. For the development of such materials and greater understanding of sodium storage mechanisms, solid electrolyte interface (SEI) formation and stability, and degradation processes, in operando methodologies are crucial.
Among the techniques available for in operando analysis, nuclear magnetic resonance spectroscopy (NMR) and imaging (MRI) are becoming increasingly used to characterize the chemical composition of battery materials, study the growth and distribution of dendrites, and investigate battery storage and degradation mechanisms. In situ and in operando 1H, 7Li and 23Na NMR and MRI have recently been used to study LIBs and NIBs, identifying chemical changes in Li and Na species respectively, in metallic, quasimetallic and electrolytic environment as well as directly and indirectly studying dendrite formation in both systems.[2-4] The ability of NMR and MRI to probe battery systems across multiple environments can further be complemented by the enhanced spatial resolution of micro-computed X-ray tomography (μ-CT) which can provide insight into battery material microstructure and defect distribution.
Here, we report in operando 1H and 7Li NMR and MRI experiments that investigate LIB performance, and the identification of changes in the Li signal during charge cycling, as well as the observation of signals in both 1H and 7Li NMR spectra that we attribute to diminishing battery performance, capacity loss and degradation. Additionally, recent operando methodology are adapted and implemented to study Sn based anodes in NIBs. 23Na spectroscopy is performed to monitor the formation and evolution of peaks assigned to stages of Na insertion into Sn, while 1H MRI is used to indirectly visualize the volume expansion of Sn anodes during charge cycling. Battery operation and degradation is further explored in these NIBs, using μ-CT, where the anode is directly visualized to a higher resolution and the loss of electrolyte in the cell, during cycling is observed
T2 - 17th International Conference on Magnetic Resonance Microscopy
CY - Singapore
DA - 27.08.2023
KW - Sodium ion battery
KW - Lithium ion battery
KW - NMR
KW - MRI
KW - Tomography
PY - 2023
AN - OPUS4-58421
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Gupta, Kanhaiya
A1 - Waske, Anja
T1 - Classification of pores from micro-XCT data of additively manufactured components prepared by laser powder bed fusion.
N2 - Laser powder bed fusion (PBF-LB/M) is a metal-based additive manufacturing (AM) process that utilizes a laser to melt powder particles selectively and form the desired product through a layer-by-layer fabrication process. It allows access to a vast new design space and can produce parts with far greater geometrical complexity than traditional methods. However, PBF-LB/M induces inevitable microstructural defects, such as voids and pores, that can adversely affect the quality and performance of the manufactured components. Hence, knowledge of pore formation, types, and suppression is essential for successful future AM applications. This research investigates the formation of different types of pores and their quantification from X-ray micro-computed tomography images of a formerly reported sample. It also examines the influence of the volumetric energy density (VED) on the size, shape, and location of pores for 316L stainless steel parts produced by the PBF-LB/M process.
T2 - FEMS EUROMAT 2023
CY - Frankfurt a. M., Germany
DA - 03.09.2023
KW - Additive manufacturing
KW - Laser Powder Bed Fusion
KW - X-ray Computed Tomography
PY - 2023
AN - OPUS4-58337
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Bustamante, Joana
A1 - Naik, Aakash Ashok
A1 - Ueltzen, Katharina
A1 - Ertural, Christina
A1 - George, Janine
T1 - Thermodynamic and Thermoelectric Properties of the Canfieldite, (Ag8SnS6 ), in the Quasi-Harmonic Approximation
N2 - Argyrodite-type materials have lately sparked a lot of research interest due to their thermoelectric properties. One promising candidate is canfieldite (Ag8SnS6), which has a Pna21 orthorhombic crystal structure at room temperature (RT). Recently, Slade group found a new low-temperature (LT) phase transition of canfieldite at 120K. Therefore, we investigate structural, vibrational and thermodynamic properties of Ag8SnS6 at room- and low-temperature employing density-functional theory (DFT) and lattice dynamics computations. Thermal properties calculations were based on the quasi-harmonic approximation (QHA) as implemented in phonopy. We achieve good agreement with experiments. Lattice parameters were overestimated by 2%, and thermal properties such as the constant-pressure heat capacity Cp are very close to experimental measurements. Our simulations also reveal a possible new phase transition at around 312 K. Furthermore, we compared RT and LT Ag8SnS6 Grüneisen parameters with some argyrodites analogues, Ag8TS6 (T = Si, Ge, Ti and Sn), finding a relationship between the anharmonicity and low thermal conductivity.
T2 - TDEP Summer School 2023 (TDEP2023: Finite-temperature and anharmonic response properties of solids in theory and practice)
CY - Linköping, Sweden
DA - 20.08.2023
KW - Thermoelectric materials
KW - DFT
KW - QHA
KW - Grüneisen parameter
PY - 2023
AN - OPUS4-58147
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Miliūtė, Aistė
A1 - George, Janine
A1 - Mieller, Björn
A1 - Stawski, Tomasz
T1 - ZrV2O7 negative thermal expansion (NTE) material
N2 - Zirconium vanadate (ZrV2O7) is a well-known negative thermal expansion (NTE) material that exhibits significant isotropic contraction over a broad temperature range (~150°C < T < 800°C). Therefore, it can be used to create composites with controllable expansion coefficients and prevent thermal stress, fatigue, cracking, and deformation at interfaces. We implement interdisciplinary research to analyze such material. We study the influence of the synthesis methods and their parameters on the sample's purity, crystallinity, and homogeneity. Moreover, we implement ab initio-based vibrational computations with partially treated anharmonicity in combination with experimental methods to follow temperature-induced structural changes and rationalize the negative thermal expansion in this material, including the influence of the local structure disorder.
T2 - SALSA Make and Measure Conference
CY - Berlin, Germany
DA - 13.09.2023
KW - NTE
KW - Composites
KW - TEM
PY - 2023
AN - OPUS4-58367
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Bustamante Pineda, Joana Cecibel
A1 - George, Janine
T1 - Sulfide-Argyrodites: Thermal properties within the QHA
N2 - Argyrodite-type materials have lately sparked a lot of research interest due to their thermoelectric properties. One promising candidate is canfieldite (Ag8SnS6), which has a Pna21 orthorhombic crystal structure at room temperature (RT). Recently, experimentalists have found a new low-temperature (LT) phase transition of canfieldite at 120K. Therefore, we investigate structural, vibrational and thermodynamic properties of Ag8SnS6 at room- and low-temperature employing density-functional theory (DFT) and lattice dynamics computations. Thermal properties calculations were based on the quasi-harmonic approximation (QHA) as implemented in phonopy. We achieve good agreement with experiments. Lattice parameters were overestimated by 2%, and thermal properties such as the constant-pressure heat capacity Cp are very close to experimental measurements. Our simulations also reveal a possible new phase transition at around 312 K. Furthermore, we compared RT and LT Ag8SnS6 Grüneisen parameters with some argyrodites analogues, Ag8TQ6 (T = Si, Ge, Ti and Sn; Q = S, Se), finding a relationship between the anharmonicity and low thermal conductivity.
T2 - SALSA Make and Measure Conference
CY - Berlin, Germany
DA - 13.09.2023
KW - Thermoelectric materials
KW - DFT
KW - QHA
KW - Grüneisen parameter
PY - 2023
AN - OPUS4-58368
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Hildebrandt, R.
A1 - Seifert, M.
A1 - George, Janine
A1 - Blaurock, S.
A1 - Botti, S.
A1 - Krautscheid, H.
A1 - Grundmann, M.
A1 - Sturm, C.
T1 - Determination of acoustic phonon anharmonicities via second-order Raman scattering in CuI
N2 - We demonstrate the determination of anharmonic acoustic phonon properties via second-order Raman scattering exemplarily on copper iodide single crystals. The origin of multi-phonon features from the second-order Raman spectra was assigned by the support of the calculated 2-phonon density of states. In this way, the temperature dependence of acoustic phonons was determined down to 10\,K. To determine independently the harmonic contributions of respective acoustic phonons, density functional theory (DFT) in quasi-harmonic approximation was used. Finally, the anharmonic contributions were determined. The results are in agreement with earlier publications and extend CuI's determined acoustic phonon properties to lower temperatures with higher accuracy. This approach demonstrates that it is possible to characterize the acoustic anharmonicities via Raman scattering down to zero-temperature renormalization constants of at least 0.1cm−1.
KW - DFT
KW - Quasi-harmonic approximation
KW - Raman
KW - Phonons
KW - Anharmonicity
PY - 2023
UR - https://arxiv.org/abs/2305.18931
SP - 1
EP - 14
AN - OPUS4-58369
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Ertural, Christina
A1 - Deringer, V.
A1 - George, Janine
T1 - Automation of machine learning driven interatomic potential generation for predicting vibrational properties
N2 - Knowing phonon properties is beneficial for predicting low thermal conductivity thermoelectric materials. Employing DFT consumes lots of computational resources. Using ML-driven interatomic potentials (MLIP, e.g., GAP) opens up a faster route, but most potentials are specifically tailored to a certain compound. We aim to generalize the MLIP generation in a Python code-based workflow, combining automatic DFT runs with automated GAP fits. Automation enables easier tests, benchmarks, and validation.
T2 - SALSA Make and Measure Conference: Interfaces
CY - Berlin, Germany
DA - 13.09.2023
KW - Interatomic potentials
KW - Machine learning
KW - Phonons
KW - Thermoelectrics
KW - Automated workflows
PY - 2023
AN - OPUS4-58374
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bernardes, C. E. S.
A1 - Feliciano, I.O.
A1 - Naese, Christoph
A1 - Emmerling, Franziska
A1 - Minas da Piedade, M.
T1 - Energetics of dehydroepiandrosterone polymorphs I and II from solution and drop-sublimation Calvet microcalorimetry measurements
N2 - The lattice enthalpies and monotropic relationship of two dehydroepiandrosterone (DEHA) polymorphs (forms I and II) were evaluated through a combination of differential scanning calorimetry (DSC), isothermal solution microcalorimetry, and drop-sublimation Calvet microcalorimetry experiments. The standard molar enthalpy of transition between both forms was determined as ΔtrsHom (II→I, 298.15 K) = - 0.90 ± 0.07 kJ mol-1 and ΔtrsHom (II→I, 417.8 K) = - 1.7 ± 1.0 kJ mol- 1, from measurements of standard molar enthalpies of solution in dimethyl sulfoxide and enthalpies of fusion, respectively. Drop-sublimation Calvet microcalorimetry experiments on form I led to ΔsubHom (cr I, 298.15 K) = 132.0±3.3 kJ mol - 1. This result, when combined with the more precise ΔtrsHom (II→I) value obtained by solution calorimetry, afforded ΔsubHom (cr II, 298.15 K) = 131.1±3.3 kJ mol - 1. The overall data indicate that on enthalpic grounds form I is more stable than form II from 298.15 K up to fusion. This conclusion, and the fact that DSC experiments indicated that form I has also a considerably higher temperature fusion, namely, Tfus(cr I)= 422.5±0.2 K and Tfus(cr II) = 413.1±0.2 K, suggest that the two polymorphs are monotropically related.
KW - Calorimetry
KW - Polymorphism
KW - Enthalpy of solution
KW - Enthalpy of sublimation
KW - Thermochemistry
KW - Lattice enthalpy
PY - 2023
U6 - https://doi.org/10.1016/j.jct.2023.107137
SN - 0021-9614
SN - 1096-3626
VL - 186
SP - 1
EP - 7
PB - Elsevier
AN - OPUS4-58418
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
A1 - Naik, Aakash Ashok
A1 - Ertural, Christina
A1 - Dhamrait, Nidal
A1 - Benner, Philipp
T1 - A Quantum-Chemical Bonding Database for Solid-State Materials
N2 - A deep insight into the chemistry and nature of individual chemical bonds is essential for understanding materials. Bonding analysis is expected to provide important features for large-scale data analysis and machine learning of material properties. Such information on chemical bonds can be calculated using the LOBSTER (www.cohp.de) software package, which post-processes data from modern density functional theory computations by projecting plane wave-based wave functions onto a local atomic orbital basis. We have performed bonding analysis on 1520 compounds (insulators and semiconductors) using a fully automated workflow combining the VASP and LOBSTER software packages. We then automatically evaluated the data with LobsterPy (https://github.com/jageo/lobsterpy) and provide results as a database. The projected densities of states and bonding indicators are benchmarked on VASP projections and available heuristics, respectively. Lastly, we illustrate the predictive power of bonding descriptors by constructing a machine-learning model for phononic properties, which shows an increase in prediction accuracies by 27 % (mean absolute errors) compared to a benchmark model differing only by not relying on any quantum-chemical bonding features.
T2 - Sommersymposium des Fördervereins Chemieolympiade
CY - Online meeting
DA - 15.04.2023
KW - Automation
KW - Chemical Bonds
KW - DFT
KW - Quantum Chemistry
PY - 2023
AN - OPUS4-57310
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Naik, Aakash Ashok
A1 - Ertural, Christina
A1 - Dhamrait, Nidal
A1 - Benner, Phillip
A1 - George, Janine
T1 - Quantum-Chemical Bonding Database (Unprocessed data : Part 8)
N2 - This data is associated with the manuscript "A Quantum-Chemical Bonding Database for Solid-State Materials."
Refer to mpids.txt to see data related to which compounds are available in the tar file. (mp-xxx refer to Materials Project ID)
KW - Bonding analysis
KW - Automation
KW - Materials Informatics
KW - Computational Chemistry
KW - Database
PY - 2023
U6 - https://doi.org/10.5281/zenodo.7852823
PB - Zenodo
CY - Geneva
AN - OPUS4-57448
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Data-driven chemical understanding with geometrical and quantum-chemical bonding analysis
N2 - Talk about my recent research on data-driven chemical understanding with geometrical and quantum-chemical bonding analysis.
T2 - Donnerstagskolloquium IPC/IAAC
CY - Münster, Germany
DA - 04.05.2023
KW - Automation
KW - Machine learning
KW - Bonding Analysis
PY - 2023
AN - OPUS4-57431
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Naik, Aakash Ashok
A1 - Ertural, Christina
A1 - Dhamrait, Nidal
A1 - Benner, Phillip
A1 - George, Janine
T1 - A Quantum-Chemical Bonding Database for Solid-State Materials (JSONS: Part 1)
N2 - This database consists of bonding data computed using Lobster for 1520 solid-state compounds consisting of insulators and semiconductors. It consists of two kinds of json files. Smaller lightweight JSONS consists of summarized bonding information for each of the compounds. The files are named as per ID numbers in the materials project database.
Here we provide also the larger computational data json files for 700 compounds. This files consists of all important LOBSTER computation output files data stored as dictionary.
KW - Bonding analysis
KW - Automation
KW - Materials Informatics
KW - Computational Chemistry
KW - Database
PY - 2023
U6 - https://doi.org/10.5281/zenodo.7794811
PB - Zenodo
CY - Geneva
AN - OPUS4-57439
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Naik, Aakash Ashok
A1 - Ertural, Christina
A1 - Dhamrait, Nidal
A1 - Benner, Phillip
A1 - George, Janine
T1 - A Quantum-Chemical Bonding Database for Solid-State Materials (JSONS: Part 2)
N2 - This database consists of bonding data computed using Lobster for 1520 solid-state compounds consisting of insulators and semiconductors. The files are named as per ID numbers in the materials project database.
Here we provide the larger computational data JSON files for the rest of the 820 compounds. This file consists of all important LOBSTER computation output files data stored as a dictionary.
KW - Bonding analysis
KW - Automation
KW - Materials Informatics
KW - Computational Chemistry
KW - Database
PY - 2023
U6 - https://doi.org/10.5281/zenodo.7821727
PB - Zenodo
CY - Geneva
AN - OPUS4-57440
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Naik, Aakash Ashok
A1 - Ertural, Christina
A1 - Dhamrait, Nidal
A1 - Benner, Phillip
A1 - George, Janine
T1 - Quantum-Chemical Bonding Database (Unprocessed data : Part 1)
N2 - This data is associated with the manuscript "A Quantum-Chemical Bonding Database for Solid-State Materials."
Refer to mpids.txt to see data related to which compounds are available in the tar file. (mp-xxx refer to Materials Project ID)
Refer to README.md file instructions to reproduce the data.
KW - Bonding analysis
KW - Automation
KW - Materials Informatics
KW - Computational Chemistry
KW - Database
PY - 2023
U6 - https://doi.org/10.5281/zenodo.7852082
PB - Zenodo
CY - Geneva
AN - OPUS4-57441
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Naik, Aakash Ashok
A1 - Ertural, Christina
A1 - Dhamrait, Nidal
A1 - Benner, Phillip
A1 - George, Janine
T1 - Quantum-Chemical Bonding Database (Unprocessed data : Part 2)
N2 - This data is associated with the manuscript "A Quantum-Chemical Bonding Database for Solid-State Materials."
Refer to mpids.txt to see data related to which compounds are available in the tar file. (mp-xxx refer to Materials Project ID)
KW - Bonding analysis
KW - Automation
KW - Materials Informatics
KW - Computational Chemistry
KW - Database
PY - 2023
U6 - https://doi.org/10.5281/zenodo.7852107
PB - Zenodo
CY - Geneva
AN - OPUS4-57442
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Naik, Aakash Ashok
A1 - Ertural, Christina
A1 - Dhamrait, Nidal
A1 - Benner, Phillip
A1 - George, Janine
T1 - Quantum-Chemical Bonding Database (Unprocessed data : Part 3)
N2 - This data is associated with the manuscript "A Quantum-Chemical Bonding Database for Solid-State Materials."
Refer to mpids.txt to see data related to which compounds are available in the tar file. (mp-xxx refer to Materials Project ID)
KW - Bonding analysis
KW - Automation
KW - Materials Informatics
KW - Computational Chemistry
KW - Database
PY - 2023
U6 - https://doi.org/10.5281/zenodo.7852791
PB - Zenodo
CY - Geneva
AN - OPUS4-57443
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Naik, Aakash Ashok
A1 - Ertural, Christina
A1 - Dhamrait, Nidal
A1 - Benner, Phillip
A1 - George, Janine
T1 - Quantum-Chemical Bonding Database (Unprocessed data : Part 4)
N2 - This data is associated with the manuscript "A Quantum-Chemical Bonding Database for Solid-State Materials."
Refer to mpids.txt to see data related to which compounds are available in the tar file. (mp-xxx refer to Materials Project ID)
KW - Bonding analysis
KW - Automation
KW - Materials Informatics
KW - Computational Chemistry
KW - Database
PY - 2023
U6 - https://doi.org/10.5281/zenodo.7852798
PB - Zenodo
CY - Geneva
AN - OPUS4-57444
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Naik, Aakash Ashok
A1 - Ertural, Christina
A1 - Dhamrait, Nidal
A1 - Benner, Phillip
A1 - George, Janine
T1 - Quantum-Chemical Bonding Database (Unprocessed data : Part 5)
N2 - This data is associated with the manuscript "A Quantum-Chemical Bonding Database for Solid-State Materials."
Refer to mpids.txt to see data related to which compounds are available in the tar file. (mp-xxx refer to Materials Project ID)
KW - Bonding analysis
KW - Automation
KW - Materials Informatics
KW - Computational Chemistry
KW - Database
PY - 2023
U6 - https://doi.org/10.5281/zenodo.7852806
PB - Zenodo
CY - Geneva
AN - OPUS4-57445
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Naik, Aakash Ashok
A1 - Ertural, Christina
A1 - Dhamrait, Nidal
A1 - Benner, Phillip
A1 - George, Janine
T1 - Quantum-Chemical Bonding Database (Unprocessed data : Part 6)
N2 - This data is associated with the manuscript "A Quantum-Chemical Bonding Database for Solid-State Materials."
Refer to mpids.txt to see data related to which compounds are available in the tar file. (mp-xxx refer to Materials Project ID)
KW - Bonding analysis
KW - Automation
KW - Materials Informatics
KW - Computational Chemistry
KW - Database
PY - 2023
U6 - https://doi.org/10.5281/zenodo.7852808
PB - Zenodo
CY - Geneva
AN - OPUS4-57446
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Naik, Aakash Ashok
A1 - Ertural, Christina
A1 - Dhamrait, Nidal
A1 - Benner, Phillip
A1 - George, Janine
T1 - Quantum-Chemical Bonding Database (Unprocessed data : Part 7)
N2 - This data is associated with the manuscript "A Quantum-Chemical Bonding Database for Solid-State Materials."
Refer to mpids.txt to see data related to which compounds are available in the tar file. (mp-xxx refer to Materials Project ID)
KW - Bonding analysis
KW - Automation
KW - Materials Informatics
KW - Computational Chemistry
KW - Database
PY - 2023
U6 - https://doi.org/10.5281/zenodo.7852820
PB - Zenodo
CY - Geneva
AN - OPUS4-57447
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pauw, Brian Richard
A1 - Laskina, Sofya
A1 - Naik, Aakash Ashok
A1 - Smales, Glen Jacob
A1 - George, Janine
A1 - Breßler, Ingo
A1 - Benner, Philipp
T1 - "Ultima Ratio": Simulating wide-range X-ray scattering and diffraction
N2 - We demonstrate a strategy for simulating wide-range X-ray scattering patterns, which spans the small- and wide scattering angles as well as the scattering angles typically used for Pair Distribution Function (PDF) analysis. Such simulated patterns can be used to test holistic analysis models, and, since the diffraction intensity is on the same scale as the scattering intensity, may offer a novel pathway for determining the degree of crystallinity.
The "Ultima Ratio" strategy is demonstrated on a 64-nm Metal Organic Framework (MOF) particle, calculated from Q < 0.01 1/nm up to Q < 150 1/nm, with a resolution of 0.16 Angstrom. The computations exploit a modified 3D Fast Fourier Transform (3D-FFT), whose modifications enable the transformations of matrices at least up to 8000^3 voxels in size. Multiple of these modified 3D-FFTs are combined to improve the low-Q behaviour. The resulting curve is compared to a wide-range scattering pattern measured on a polydisperse MOF powder. While computationally intensive, the approach is expected to be useful for simulating scattering from a wide range of realistic, complex structures, from (poly-)crystalline particles to hierarchical, multicomponent structures such as viruses and catalysts.
KW - X-ray
KW - Simulation
KW - 3D Fourier Transform
KW - High resolution
KW - XRD
KW - SAXS
KW - PDF
KW - Total scattering
KW - X-ray scattering
KW - Metal organic framework
KW - Electron density map
KW - FFT
PY - 2023
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-572067
VL - Cornell University
SP - 1
EP - 12
PB - Ithaca, NY
AN - OPUS4-57206
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Pauw, Brian Richard
A1 - Laskina, Sofya
A1 - Naik, Aakash Ashok
A1 - Smales, Glen Jacob
A1 - George, Janine
A1 - Breßler, Ingo
A1 - Benner, Philipp
T1 - Jupyter notebook and VASP calculation details accompanying the manuscript: "Ultima Ratio: Simulating wide-range X-ray scattering and diffraction"
N2 - ## Summary:
This notebook and associated datasets (including VASP details) accompany a manuscript available on the ArXiv (https://doi.org/10.48550/arXiv.2303.13435) and hopefully soon in a journal as short communication as well. Most of the details needed to understand this notebook are explained in that paper with the same title as above. For convenience, the abstract is repeated here:
## Paper abstract:
We demonstrate a strategy for simulating wide-range X-ray scattering patterns, which spans the small- and wide scattering angles as well as the scattering angles typically used for Pair Distribution Function (PDF) analysis. Such simulated patterns can be used to test holistic analysis models, and, since the diffraction intensity is presented coupled to the scattering intensity, may offer a novel pathway for determining the degree of crystallinity.
The ``Ultima Ratio'' strategy is demonstrated on a 64-nm Metal Organic Framework (MOF) particle, calculated from $Q<0.01$\,$\mathrm{nm}^{-1}$ up to $Q\approx150$\,$\mathrm{nm}^{-1}$, with a resolution of 0.16\,\AA. The computations exploit a modified 3D Fast Fourier Transform (3D-FFT), whose modifications enable the transformations of matrices at least up to $8000^3$ voxels in size. Multiple of these modified 3D-FFTs are combined to improve the low-$Q$ behaviour.
The resulting curve is compared to a wide-range scattering pattern measured on a polydisperse MOF powder.
While computationally intensive, the approach is expected to be useful for simulating scattering from a wide range of realistic, complex structures, from (poly-)crystalline particles to hierarchical, multicomponent structures such as viruses and catalysts.
KW - X-ray
KW - Simulation
KW - Scattering
KW - MOUSE
KW - Nanomaterials
KW - XRD
KW - SAXS
KW - PDF
KW - total scattering
KW - 3D Fourier Transform
KW - High Resolution
KW - FFT
PY - 2023
UR - https://doi.org/10.48550/arXiv.2303.13435
U6 - https://doi.org/10.5281/zenodo.7764044
PB - Zenodo
CY - Geneva
AN - OPUS4-57207
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - VIDEO
A1 - Pauw, Brian Richard
T1 - "Ultima Ratio": Multi-scale, high-resolution 3D-FFT scattering pattern simulations
N2 - This talk highlights a proof-of-concept that demonstrates the ability to calculate high-resolution Fourier transforms. These can be combined with multi-scale modeling to simulate scattering over a wide range, from small-angle scattering to XRD and PDF.
The preprint documenting this is available on the ArXiv here:
https://doi.org/10.48550/arXiv.2303.13435
The Jupyter notebook, VASP calculation details and MOUSE measured scattering patterns are available from this Zenodo repository: https://dx.doi.org/10.5281/zenodo.7764045
KW - Video
KW - Simulation
KW - High-resolution
KW - Fourier Transform
KW - 3D FFT
KW - Nanomaterial
KW - Metal organic framework
KW - MOF
KW - SAXS
KW - XRD
KW - PDF
KW - X-ray diffraction
KW - Pair distribution function
KW - Small-angle X-ray scattering
PY - 2023
UR - https://www.youtube.com/watch?v=lEApkOqR5e8
PB - YouTube, LLC
CY - San Bruno, CA, USA
AN - OPUS4-57212
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Linberg, Kevin
A1 - Michalchuk, Adam
A1 - Emmerling, Franziska
T1 - Controlled Polymorphism by Elevated Temperature Ball Milling
N2 - Mechanochemistry provides polymorphs that are difficult to obtain by conventional solution-based methods. Based on the nicotinamide and pimelic acid cocrystal, we demonstrated that the ball size, frequency, and temperature are essential parameters. Our results indicate that fine-tuning the energy input during a mechanochemical reaction can provide control over polymorphism.
T2 - Bessy User Meeting 2023
CY - Berlin, Germany
DA - 22.06.2023
KW - Mechanochemistry
KW - Temperature
KW - Cocrystal
KW - Energy input
KW - Polymorph
PY - 2023
AN - OPUS4-57985
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Heinekamp, Christian
A1 - Guiherme Buzanich, Ana
A1 - Ahrens, Mike
A1 - Emmerling, Franziska
A1 - Braun, Thomas
T1 - Zirconium chloro fluoride as catalyst for C-F bond activation and HF transfer of fluoroalkanes
N2 - In this work1, we have successfully synthesised amorphous zirconium chloro fluoride (ZCF), which exhibits medium lewis acidity. In addition to investigating the local coordination sphere around the Zr atoms and the material properties, we were able to establish a catalytic behavior of ZCF in C-F bond activation reactions. We present the first heterogeneous catalyst that performs dehydrofluorination of a fluoroalkane and consecutive hydrofluorination of an alkyne at room temperature.
T2 - RSC Poster 2024
CY - Online meeting
DA - 05.03.2024
KW - ZCF
PY - 2024
AN - OPUS4-59619
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Understanding and Machine Learning of Materials Properties with Quantum-Chemical Bonding Analysis
N2 - Bonds and local atomic environments are crucial descriptors for material properties. They have been used to create design rules for materials and are used as features in machine learning of material properties. This talk will show how our recently developed tools, that automatically perform quantum chemical bond analysis and enable the study of chemical bonds and local atomic environments, accelerate and improve the development of such heuristics and machine-learned models for materials properties.
T2 - Accelerate Conference 2023
CY - Toronto, Canada
DA - 22.08.2023
KW - Automation
KW - DFT
KW - Bonds
PY - 2023
AN - OPUS4-58131
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Miliūtė, Aistė
A1 - Bustamante, Joana
A1 - Mieller, Björn
A1 - Stawski, Tomasz
A1 - George, Janine
A1 - Knoop, F.
T1 - High-quality zirconium vanadate samples for negative thermal expansion (NTE) analysis
N2 - Zirconium vanadate (ZrV2O7) is a well-known negative thermal expansion (NTE) material which exhibits significant isotropic contraction over a broad temperature range (~150°C < T < 800°C). The linear thermal expansion coefficient of ZrV2O7 is −7.1×10-6 K-. Therefore, it can be used to create composites with controllable expansion coefficients and prevent destruction by thermal shock.
Material characterization, leading to application, requires pure, homogenous samples of high crystallinity via a reliable synthesis route. While there is a selection of described syntheses in the literature, it still needs to be addressed which synthesis route leads to truly pure and homogenous samples. Here, we study the influence of the synthesis methods (solid-state, sol-gel, solvothermal) and their parameters on the sample's purity, crystallinity, and homogeneity. The reproducibility of results and data obtained with scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry, and thermogravimetric analysis (DSC/TGA) were analyzed extensively. The sol-gel method proves superior to the solid-state method and produces higher-quality samples over varying parameters. Sample purity also plays an important role in NTE micro and macro-scale characterizations that explain the impact of porosity versus structural changes.
Moreover, we implement ab-initio-based vibrational computations with partially treated anharmonicity (quasi-harmonic approximation, temperature-dependent effective harmonic potentials) in combination with experimental methods to follow and rationalize the negative thermal expansion in this material, including the influence of the local structure disorder, microstructure, and defects. Khosrovani et al. and Korthuis et al., in a series of diffraction experiments, attributed the thermal contraction of ZrV2O7 to the transverse thermal motion of oxygen atoms in V-O-V linkages. In addition to previous explanations, we hypothesize that local disorder develops in ZrV2O7 crystals during heating.
We are working on the experimental ZrV2O7 development and discuss difficulties one might face in the process as well as high-quality sample significance in further investigation. The obtained samples are currently used in the ongoing research of structure analysis and the negative thermal expansion mechanism.
T2 - 4th International Symposium on Negative Thermal Expansion and Related Materials (ISNTE-4)
CY - Padua, Italy
DA - 04.07.2023
KW - NTE
KW - Sol-gel
KW - Solid-state
KW - Ab-initio
KW - TDEP
PY - 2023
AN - OPUS4-58132
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Miliūtė, Aistė
A1 - Bustamante, Joana
A1 - Mieller, Björn
A1 - Stawski, Tomasz
A1 - George, Janine
A1 - Knoop, F.
T1 - High-quality zirconium vanadate samples for negative thermal expansion (NTE) analysis
N2 - Zirconium vanadate (ZrV2O7) is a well-known negative thermal expansion (NTE) material which exhibits significant isotropic contraction over a broad temperature range (~150°C < T < 800°C). The linear thermal expansion coefficient of ZrV2O7 is −7.1×10-6 K-. Therefore, it can be used to create composites with controllable expansion coefficients and prevent destruction by thermal shock.
Material characterization, leading to application, requires pure, homogenous samples of high crystallinity via a reliable synthesis route. While there is a selection of described syntheses in the literature, it still needs to be addressed which synthesis route leads to truly pure and homogenous samples. Here, we study the influence of the synthesis methods (solid-state, sol-gel, solvothermal) and their parameters on the sample's purity, crystallinity, and homogeneity. The reproducibility of results and data obtained with scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry, and thermogravimetric analysis (DSC/TGA) were analyzed extensively. The sol-gel method proves superior to the solid-state method and produces higher-quality samples over varying parameters. Sample purity also plays an important role in NTE micro and macro-scale characterizations that explain the impact of porosity versus structural changes.
Moreover, we implement ab-initio-based vibrational computations with partially treated anharmonicity (quasi-harmonic approximation, temperature-dependent effective harmonic potentials) in combination with experimental methods to follow and rationalize the negative thermal expansion in this material, including the influence of the local structure disorder, microstructure, and defects. Khosrovani et al. and Korthuis et al., in a series of diffraction experiments, attributed the thermal contraction of ZrV2O7 to the transverse thermal motion of oxygen atoms in V-O-V linkages. In addition to previous explanations, we hypothesize that local disorder develops in ZrV2O7 crystals during heating.
We are working on the experimental ZrV2O7 development and discuss difficulties one might face in the process as well as high-quality sample significance in further investigation. The obtained samples are currently used in the ongoing research of structure analysis and the negative thermal expansion mechanism.
T2 - 16th International conference on materials chemistry (MC16)
CY - Dublin, Ireland
DA - 03.07.2023
KW - NTE
KW - Sol-gel
KW - Solid-state
KW - Ab-initio
KW - TDEP
PY - 2023
AN - OPUS4-58134
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Miliūtė, Aistė
A1 - Bustamante, Joana
A1 - Mieller, Björn
A1 - Stawski, Tomasz
A1 - George, Janine
A1 - Knoop, F.
T1 - High-quality zirconium vanadate samples for negative thermal expansion (NTE) analysis
N2 - Zirconium vanadate (ZrV2O7) is a well-known negative thermal expansion (NTE) material which exhibits significant isotropic contraction over a broad temperature range (~150°C < T < 800°C). The linear thermal expansion coefficient of ZrV2O7 is −7.1×10-6 K-1. Therefore, it can be used to create composites with controllable expansion coefficients and prevent destruction by thermal shock.
Material characterization, leading to application, requires pure, homogenous samples of high crystallinity via a reliable synthesis route. While there is a selection of described syntheses in the literature, it still needs to be addressed which synthesis route leads to truly pure and homogenous samples. Here, we study the influence of the synthesis methods (solid-state, sol-gel, solvothermal) and their parameters on the sample's purity, crystallinity, and homogeneity. The reproducibility of results and data obtained with scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry, and thermogravimetric analysis (DSC/TGA) were analyzed extensively. The sol-gel method proves superior to the solid-state method and produces higher-quality samples over varying parameters. Sample purity also plays an important role in NTE micro and macro-scale characterizations that explain the impact of porosity versus structural changes.
Moreover, we implement ab-initio-based vibrational computations with partially treated anharmonicity (quasi-harmonic approximation, temperature-dependent effective harmonic potentials) in combination with experimental methods to follow and rationalize the negative thermal expansion in this material, including the influence of the local structure disorder, microstructure, and defects. Khosrovani et al. and Korthuis et al., in a series of diffraction experiments, attributed the thermal contraction of ZrV2O7 to the transverse thermal motion of oxygen atoms in V-O-V linkages. In addition to previous explanations, we hypothesize that local disorder develops in ZrV2O7 crystals during heating.
We are working on the experimental ZrV2O7 development and discuss difficulties one might face in the process as well as high-quality sample significance in further investigation. The obtained samples are currently used in the ongoing research of structure analysis and the negative thermal expansion mechanism.
T2 - TDEP2023: Finite-temperature and anharmonic response properties of solids in theory and practice
CY - Linköping, Sweden
DA - 21.08.2023
KW - NTE
KW - Sol-gel
KW - Solid-state
KW - Ab-initio
KW - TDEP
PY - 2023
AN - OPUS4-58135
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Data-driven chemical understanding with bonding analysis
N2 - Bonds and local atomic environments are crucial descriptors of material properties. They have been used to create design rules and heuristics and as features in machine learning of materials properties. Implementations and algorithms (e.g., ChemEnv and LobsterEnv) for identifying local atomic environments based on geometrical characteristics and quantum-chemical bonding analysis are nowadays available. Fully automatic workflows and analysis tools have been developed to use quantum-chemical bonding analysis on a large scale. The lecture will demonstrate how our tools, that assess local atomic environments and perform automatic bonding analysis, help to develop new machine learning models and a new intuitive understanding of materials.[5,6] Furthermore, the general trend toward automation in density functional-based materials science and some of our recent contributions will be discussed.
T2 - Seminar of the Department of Chemistry at Imperial College London
CY - Online meeting
DA - 20.02.2024
KW - Automation
KW - Magnetism
KW - Bonding Analysis
KW - Machine Learning
PY - 2024
AN - OPUS4-59546
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Naik, Aakash Ashok
A1 - Ueltzen, Katharina
A1 - Ertural, Christina
A1 - Jackson, Adam J.
A1 - George, Janine
T1 - LobsterPy: A package to automatically analyze LOBSTERruns
N2 - The LOBSTER (Deringer et al., 2011;Maintz et al., 2013 ,2016 ;Nelson et al., 2020 ) software aids in extracting quantum-chemical bonding information from materials by projecting the plane-wave based wave functions from density functional theory (DFT) onto an atomic orbital basis. LobsterEnv, a module implemented in pymatgen (Ong et al., 2013) by some of the authors of this package, facilitates the use of quantum-chemical bonding information obtained from LOBSTER calculations to identify neighbors and coordination environments. LobsterPy is a Python package that offers a set of convenient tools to further analyze and summarize the LobsterEnv outputs in the form of JSONs that are easy to interpret and process. These tools enable the estimation of (anti) bonding contributions, generation of textual descriptions, and visualization of LOBSTER computation results. Since its first release, both LobsterPy and LobsterEnv capabilities have been extended significantly. Unlike earlier versions, which could only automatically analyze Crystal Orbital Hamilton Populations (COHPs) (Dronskowski & Blöchl, 1993), both can now also analyze Crystal Orbital Overlap Populations (COOP) (Hughbanks & Hoffmann, 1983) and Crystal Orbital Bond Index (COBI) (Müller et al., 2021). Extracting the information about the most important orbitals contributing to the bonds is optional, and users can enable it as needed. Additionally, bonding-based features for machinelearning (ML) studies can be engineered via the sub-packages “featurize” and “structuregraphs”. Alongside its Python interface, it also provides an easy-to-use command line interface (CLI) that runs automatic analysis of the computations and generates a summary of results and publication-ready figures. LobsterPy has been used to produce the results in Ngo et al. (2023), Chen et al. (2024), Naik et al. (2023), and it is also part of Atomate2 (2023) bonding analysis workflow for generating bonding analysis data in a format compatible with the Materials Project (Jain et al., 2013) API.
KW - Materials Science
KW - Automation
KW - Bonding Analysis
KW - Materials Properties
PY - 2024
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-595809
VL - 9
IS - 94
SP - 1
EP - 4
PB - The Open Journal
AN - OPUS4-59580
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Manoharan, Deepak
A1 - Ranjan, Subham
A1 - Emmerling, Franziska
A1 - Bhattacharya, Biswajit
A1 - Takamizawa, Satoshi
A1 - Ghosh, Soumyajit
T1 - Elasto-plastic behaviour with reversible thermosalient expansion in acrylonitrile-based organic crystals
N2 - Crystalline materials that exhibit reversible mechanical responses upon exposure to external stimuli have garnered significant attention owing to their potential applications in various fields. Herein, we report a crystal of (2Z,2′Z)-2,2′-(1,4-phenylene)bis(3-(4-bromophenyl)acrylonitrile) (DSBr), which displays simultaneous elasto-plastic behaviour and reversible thermosalient effects. While elasto-plastic behaviour is attributed to underlying packing features, reversible thermosalient expansion is attributed to uniaxial expansion mediated by heat. Exceptional length increase and contraction upon cooling is due to the restorative nature of weak interactions through a cooperative effect. The cooperative movement of molecules is reflected in the unidirectional expansion of the habit plane. Thermosalient reversible expansion–contraction in elasto-plastic crystals have not been discussed in the literature so far. Detailed analysis reported herein provides a comprehensive understanding of the underlying mechanism of flexibility and thermosalient responses. This crystal's unique blend of reversible thermal expansion with flexibility holds substantial promise for applications in flexible thermal actuators.
KW - Materials Chemistry
KW - General Chemistry
PY - 2024
U6 - https://doi.org/10.1039/D3TC04272C
SN - 2050-7526
SP - 1
EP - 11
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-59527
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Data-driven chemical understanding with bonding analysis
N2 - Bonds and local atomic environments are crucial descriptors of material properties. They have been used to create design rules and heuristics for materials. More and more frequently, they are used as features in machine learning. Implementations and algorithms (e.g., ChemEnv and LobsterEnv) for identifying these local atomic environments based on geometrical characteristics and quantum-chemical bonding analysis are nowadays available. Fully automatic workflows and analysis tools have been developed to use quantum-chemical bonding analysis on a large scale and for machine-learning approaches. The latter relates to a general trend toward automation in density functional-based materials science. The lecture will demonstrate how our tools, that assess local atomic environments, helped to test and develop heuristics and design rules and an intuitive understanding of materials.
T2 - 2023 MRS Fall Meeting & Exhibit
CY - Boston, Massachusetts, USA
DA - 26.11.2023
KW - Automation
KW - Machine learning
KW - Materials Understanding
KW - Magnetism
KW - Phonons
PY - 2023
AN - OPUS4-59002
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - Understanding mechanochemical reactions: Real-time insights and collaborative research
N2 - Mechanochemistry emerges as a potent, environmentally friendly, and straightforward approach for crafting novel multicomponent crystal systems. Various milling parameters, including milling frequency, time, filling degree of the milling jar, ball diameter, vessel size, degree of milling ball filling, and material of jars, are recognized influencers on the mechanisms and rates of product formation. Despite the growing interest in mechanochemistry, there exists a gap in understanding the mechanistic aspects of mechanochemical reactivity and selectivity. To address this, diverse analytical methods and their combinations, such as powder X-ray diffraction, X-ray absorption spectroscopy, NMR, Raman spectroscopy, and thermography, have been developed for real-time, in situ monitoring of mechanochemical transformations.
This discussion centers on our recent findings, specifically investigating the formation of (polymorphic) cocrystals and metal-organic frameworks. Through these studies, we aim to unravel the impact of milling parameters and reaction sequences on the formation mechanism and kinetics. Notably, in the mechanochemical chlorination reaction of hydantoin, normalizing kinetic profiles to the volume of the milling ball unequivocally demonstrates the conservation of milling reaction kinetics. In this ball-milling transformation, physical kinetics outweigh chemical factors in determining reaction rates. Attempting to interpret such kinetics solely through chemical terms poses a risk of misinterpretation. Our results highlight that time-resolved in situ investigations of milling reactions provide a novel avenue for fine-tuning and optimizing mechanochemical processes.
T2 - PhD Seminar
CY - Online meeting
DA - 12.10.2023
KW - Mechanochemistry
KW - In situ
PY - 2023
AN - OPUS4-59022
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Goswami, Juli Nanda
A1 - Haque, Najirul
A1 - Seikh, Asiful H.
A1 - Bhattacharya, Biswajit
A1 - Emmerling, Franziska
A1 - Bar, Nimai
A1 - Ifseisi, Ahmad A.
A1 - Biswas, Surajit
A1 - Dolai, Malay
T1 - Carboxylative cyclization of propargyl alcohols with carbon dioxide for the synthesis of α-alkylidene cyclic carbonates in presence of Co(III) schiff base complex catalyst
N2 - A cobalt(III) complex, [Co(L)3](DMF) (1) of Schiff base ligand HL, 2-((E)-(benzylimino)methyl)-4-bromophenol is prepared and single crystal X-ray structural analysis have also been performed. The structures of complex 1 showed hexa-coordinated mononuclear systems that adopt octahedral geometry. The complex has also exhibited the supramolecular networks through non-covalent interactions like H-bonding, C–Hπ stacking. Moreover, the complex 1 is very effective in the catalytic fixation of carbon dioxide in propergyl alcohols to produce α-alkylidene cyclic carbonates. The catalytic production of α-alkylidene cyclic carbonates have been carried out through carboxylative cyclization of propargyl alcohols using CO2 balloon of 1 atm pressure at 80 ◦C. Solvent free condition (green synthesis) made this catalytic protocol eco-friendly towards the environment. Utilizing various substrates of propargyl alcohols moderate to high percentage yield (62–95%) of respective α-alkylidene cyclic carbonates product have been isolated over this catalytic reaction. Besides, the theoretical calculations (DFT) was performed for the prediction of probable mechanism of the catalytic reaction
KW - Catalytic fixation of carbon dioxide
KW - Carboxylative cyclization of propargyl alcohols
KW - Cobalt (III) Schiff base complex
KW - X-ray crystal analysis
PY - 2024
U6 - https://doi.org/10.1016/j.molstruc.2023.136868
SN - 0022-2860
VL - 1296
IS - Part 1
SP - 1
EP - 8
PB - Elsevier B.V.
AN - OPUS4-58947
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - Investigating the mechanism and kinetics of the mechanochemical synthesis of multi-component systems
N2 - Mechanochemistry is a promising and environmentally friendly approach for synthesizing (novel) multicomponent crystal systems. Various milling parameters, such as milling frequency, milling time, and ball diameter have been shown to influence the mechanisms and rates of product formation. Despite increasing interest in mechanochemistry, there is still limited understanding of the underlying reactivity and selectivity mechanisms.
Various analytical techniques have been developed to gain insight into the mechanochemical transformations, including powder X-ray diffraction, X-ray adsorption spectroscopy, NMR, Raman spectroscopy and thermography. Using these techniques, we have studied the formation of (polymorphic) cocrystals, organometallic compounds and salts, and elucidated the influence of milling parameters and reaction sequences on the formation mechanism and kinetics.
For example, our study of the mechanochemical chlorination reaction of hydantoin revealed that normalisation of the kinetic profiles to the volume of the grinding ball clearly showed that physical kinetics dominate the reaction rates in a ball-milling transformation. Attempts to interpret such kinetics in purely chemical terms risk misinterpretation of the results.
Our results suggest that time-resolved in situ investigation of milling reactions is a promising way to fine-tune and optimise mechanochemical processes.
T2 - ISIC 2023
CY - Glasgow, Scotland
DA - 05.09.2023
KW - Mechanochemistry
KW - Polymorphy
KW - In situ
PY - 2023
AN - OPUS4-59023
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - Understanding mechanochemical reactions: Real-time insights and collaborative research
N2 - Mechanochemistry emerges as a potent, environmentally friendly, and straightforward approach for crafting novel multicomponent crystal systems. Various milling parameters, including milling frequency, time, filling degree of the milling jar, ball diameter, vessel size, degree of milling ball filling, and material of jars, are recognized influencers on the mechanisms and rates of product formation. Despite the growing interest in mechanochemistry, there exists a gap in understanding the mechanistic aspects of mechanochemical reactivity and selectivity. To address this, diverse analytical methods and their combinations, such as powder X-ray diffraction, X-ray absorption spectroscopy, NMR, Raman spectroscopy, and thermography, have been developed for real-time, in situ monitoring of mechanochemical transformations.
This discussion centers on our recent findings, specifically investigating the formation of (polymorphic) cocrystals and metal-organic frameworks. Through these studies, we aim to unravel the impact of milling parameters and reaction sequences on the formation mechanism and kinetics. Notably, in the mechanochemical chlorination reaction of hydantoin, normalizing kinetic profiles to the volume of the milling ball unequivocally demonstrates the conservation of milling reaction kinetics. In this ball-milling transformation, physical kinetics outweigh chemical factors in determining reaction rates. Attempting to interpret such kinetics solely through chemical terms poses a risk of misinterpretation. Our results highlight that time-resolved in situ investigations of milling reactions provide a novel avenue for fine-tuning and optimizing mechanochemical processes.
T2 - Brimingham Green chemsistry
CY - Birmingham, England
DA - 08.09.2023
KW - Mechanochemistry
KW - Green Chemistry
PY - 2023
AN - OPUS4-59024
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - Combination of complementary methods For in situ studies
N2 - This talk explores the synergistic application of complementary synchrotron methods for in situ investigations, providing a comprehensive approach to enhance analytical capabilities in materials research and characterization.
T2 - INSYNX - DEUTSCH-BRASILIANISCHER WORKSHOP ON BREAKING BOUNDARIES OF IN SITU SYNCHROTRON X-RAY METHODS
CY - Sao Paulo, Brazil
DA - 06.03.2023
KW - In situ
KW - Synchrotron
PY - 2023
AN - OPUS4-59025
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - Understanding mechanochemical reactions: Real-time insights and collaborative research
N2 - Mechanochemistry has become a compelling method for producing (new) molecule s and mate-rials, but the inner workings of the milling jars remain a fascinating mystery. Advances in this field include tailor-made chemical systems and real-time revelations using techniques such as XRD and Raman spectroscopy.
This talk will discuss our recent progress in using X-ray diffraction and sophisticated spectros-copy to observe reactions in various material systems during ball milling and extrusion in real-time.
The complexity of mechanochemical reactions spans multiple scales and requires a holistic ap-proach. The categorisation of reactions by investigative methods precedes the exploration of real-time analysis that reveals macroscopic processes using synchrotron techniques.
During this exploration, one resounding realisation remains: We are on the threshold of under-standing. The complexity of mechanochemistry requires a collective effort, drawing on the ex-pertise of a diverse community. As we unravel the web of mechanochemical phenomena, we acknowledge the collaborative nature of this ongoing journey.
T2 - CMCC Mechanochemistry Discussions
CY - Online meeting
DA - 21.09.2023
KW - Mechanochemistry
KW - In situ
PY - 2023
AN - OPUS4-59026
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - Connecting the nodes: networks and networking
N2 - This talk explores the intricate connections between scientists, focusing on the networking dynamics within the realm of metal-organic frameworks (MOFs). The study delves into the collaborative networks formed among scientists, shedding light on the synergistic relationships that contribute to advancements in MOF research.
T2 - WINS School 2023 Frameworks and networks
CY - Blossin, Germany
DA - 02.06.2023
KW - Metal-organic frameworks
PY - 2023
AN - OPUS4-59028
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Witt, Julia
T1 - Exploring innovative Materials and in situ techniques
N2 - Presentation of some projects conducted in recent years related to corrosion studies and research on electrocatalysis. The talk was part of a seminar at the University of Toronto and took place within the framework of a scientific exchange stay.
T2 - Seminar at the University of Toronto
CY - Toronto, Canada
DA - 11.10.2023
KW - Multi-principal element alloys (MPEAs)
KW - Electrocatalysis
KW - Corrosion
KW - Materials acceleration platforms (MAPs)
PY - 2023
AN - OPUS4-59029
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - Data-Driven Chemical Understanding with Bonding Analysis
N2 - Bonds and local atomic environments are crucial descriptors of material properties. They have been used to create design rules and heuristics and as features in machine learning of materials properties. Implementations and algorithms (e.g., ChemEnv and LobsterEnv) for identifying local atomic environments based on geometrical characteristics and quantum-chemical bonding analysis are nowadays available. Fully automatic workflows and analysis tools have been developed to use quantum-chemical bonding analysis on a large scale. The lecture will demonstrate how our tools, that assess local atomic environments and perform automatic bonding analysis, help to develop new machine learning models and a new intuitive understanding of materials. Furthermore, the general trend toward automation in density functional-based materials science and some of our recent contributions will be discussed.
T2 - Otaniemi Center for Atomic-scale Materials Modeling Seminar
CY - Aalto, Finland
DA - 11.03.2024
KW - Automation
KW - Materials Design
KW - Bonding Analysis
KW - Machine Learning
PY - 2024
AN - OPUS4-59671
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - George, Janine
T1 - High-throughput and automated bonding Analysis
N2 - Talk as a part of the LOBSTER CECAM SCHOOL. This talk introduced all participants to automation tools around the software LOBSTER.
T2 - CECAM LOBSTER School
CY - Aalto, Finland
DA - 12.03.2024
KW - Automation
KW - Workflows
KW - Bonding Analysis
KW - Materials Design
KW - Chemically Complex Materials
PY - 2024
AN - OPUS4-59672
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Zuffa, Caterina
A1 - Cappuccino, Chiara
A1 - Casali, Lucia
A1 - Emmerling, Franziska
A1 - Maini, Lucia
T1 - Liquid reagents are not enough for liquid assisted grinding in the synthesis of (AgBr)(n-pica) n
N2 - This study investigates the mechanochemical reactions between AgBr 3-picolylamine and 4-picolylamine. The use of different stoichiometry ratios of the reagents allows [(AgBr)(n-pica)]n and [(AgBr)2(n-pica)]n to be obtained, and we report the new structures of [(AgBr)2(3-pica)]n and [(AgBr)2(4-pica)]n which are characterized by the presence of the following: (a) infinite inorganic chains, (b) silver atom coordinated only by bromide atoms and (c) argentophilic interactions. Furthermore, we studied the interconversion of [(AgBr)(n-pica)]n/[(AgBr)2(n-pica)]n by mechanochemical and thermal properties. The in situ experiments suggest that [(AgBr)(3-pica)]n is kinetically favoured while [(AgBr)2(3-pica)]n is converted into [(AgBr)(3-pica)]n only with a high excess of the ligand. Finally, the liquid nature of the ligands is not sufficient to assist the grinding process, and the complete reaction is observed with the addition of a small quantity of acetonitrile.
KW - Mechanochemistry
KW - Complex
PY - 2024
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-594755
SN - 1463-9076
SP - 1
EP - 10
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-59475
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - Why shaken, not stirred, makes the difference: insights into mechanochemical reactions from in situ investigations
N2 - Mechanochemistry is an effective, environmentally benign, and facile method for the synthesis of new multicomponent crystal systems. Different milling parameters are known to affect the mechanisms and rates of product formation: milling frequency, milling time, filling degree of the milling jar, ball diameter and vessel size, degree of milling ball filling, and material of jars. The increasing interest in mechanochemistry is contrasted by a limited mechanistic understanding of the mechanochemical reactivity and selectivity.
Different analytical methods and their combinations have been developed for the time resolved in situ monitoring of mechanochemical transformations, including powder X-ray diffraction, X-ray adsorption spectroscopy, NMR, Raman spectroscopy, and thermography.
Here we will discuss our recent results investigating the formation of (poly-morphic) cocrystals[1,3], metal-organic compounds, and salts, thereby elucidating the influence of milling parameters and reaction sequences on the formation mechanism and kinetics. For the mechanochemical chlorination reaction of hydantoin normalizing the kinetic profiles to the volume of the milling ball showed clearly that milling reaction kinetics are conserved. Here physical kinetics dominate reaction rates in a ball-milling transformation. Attempting to interpret such kinetics in purely chemical terms risk misinterpreting the results.
Our results indicate that time-resolved in situ investigation of milling reactions offer a new approach to tune and optimize mechanochemical processes.
T2 - GdCh Vortrag Universität Potsdam
CY - Potsdam, Germany
DA - 05.06.2023
KW - Mechanochemistry
KW - In Situ
PY - 2023
AN - OPUS4-58982
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rosen, Andrew S.
A1 - Gallant, Max
A1 - George, Janine
A1 - Riebesell, Janosh
A1 - Sahasrabuddhe, Hrushikesh
A1 - Shen, Jimmy-Xuan
A1 - Wen, Mingjian
A1 - Evans, Matthew L.
A1 - Petretto, Guido
A1 - Waroquiers, David
A1 - Rignanese, Gian-Marco
A1 - Persson, Kristin A.
A1 - Jain, Anubhav
A1 - Ganose, Alex M.
T1 - Jobflow: Computational Workflows Made Simple
N2 - We present Jobflow, a domain-agnostic Python package for writing computational workflows tailored for high-throughput computing applications. With its simple decorator-based approach, functions and class methods can be transformed into compute jobs that can be stitched together into complex workflows. Jobflow fully supports dynamic workflows where the full acyclic graph of compute jobs is not known until runtime, such as compute jobs that launch
other jobs based on the results of previous steps in the workflow. The results of all Jobflow compute jobs can be easily stored in a variety of filesystem- and cloud-based databases without the data storage process being part of the underlying workflow logic itself. Jobflow has been intentionally designed to be fully independent of the choice of workflow manager used to dispatch the calculations on remote computing resources. At the time of writing, Jobflow
workflows can be executed either locally or across distributed compute environments via an adapter to the FireWorks package, and Jobflow fully supports the integration of additional workflow execution adapters in the future.
KW - Automation
KW - Workflow
KW - Computational Materials Science
KW - Computations
KW - Software
PY - 2024
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-593104
VL - 9
IS - 93
SP - 1
EP - 7
PB - The Open Journal
AN - OPUS4-59310
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Rosen, Andrew S.
A1 - Gallant, Max
A1 - George, Janine
A1 - Riebesell, Janosh
A1 - Sahasrabuddhe, Hrushikesh
A1 - Shen, Jimmy-Xuan
A1 - Wen, Mingjian
A1 - Evans, Matthew L.
A1 - Petretto, Guido
A1 - Waroquiers, David
A1 - Rignanese, Gian-Marco
A1 - Persson, Kristin A.
A1 - Jain, Anubhav
A1 - Ganose, Alex M.
T1 - Jobflow: Computational Workflows Made Simple
N2 - Jobflow is a free, open-source library for writing and executing workflows. Complex workflows can be defined using simple python functions and executed locally or on arbitrary computing resources using the FireWorks workflow manager.
Some features that distinguish jobflow are dynamic workflows, easy compositing and connecting of workflows, and the ability to store workflow outputs across multiple databases.
KW - Automation
KW - Workflows
KW - Computational Materials Science
PY - 2024
U6 - https://doi.org/10.5281/zenodo.10466868
PB - Zenodo
CY - Geneva
AN - OPUS4-59313
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Hildebrandt, R
A1 - Seifert, M
A1 - George, J
A1 - Blaurock, S
A1 - Botti, S
A1 - Krautscheid, H
A1 - Grundmann, M
A1 - Sturm, C
T1 - Determination of acoustic phonon anharmonicities via second-order Raman scattering in CuI
N2 - We demonstrate the determination of anharmonic acoustic phonon properties via second-order Raman scattering exemplarily on copper iodide single crystals. The origin of multi-phonon features from the second-order Raman spectra was assigned by the support of the calculated 2-phonon density of states. In this way, the temperature dependence of acoustic phonons was determined down to 10 K. To determine independently the harmonic contributions of respective acoustic phonons, density functional theory in quasi-harmonic approximation was used. Finally, the anharmonic contributions were determined. The results are in agreement with earlier publications and extend CuI’s determined acoustic phonon properties to lower temperatures with higher accuracy. This approach demonstrates that it is possible to characterize the acoustic anharmonicities via Raman scattering down to zero-temperature renormalization constants of at least 0.1 cm−1.
KW - Thermoelectrics
KW - Thermal transport
KW - Phonon interactions
KW - Density functional theory
KW - Phonons
PY - 2023
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-593164
SN - 1367-2630
VL - 25
IS - 12
SP - 1
EP - 12
PB - IOP Publishing
AN - OPUS4-59316
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Linberg, Kevin
A1 - Szymoniak, Paulina
A1 - Schönhals, Andreas
A1 - Emmerling, Franziska
A1 - Michalchuk, Adam A. L.
T1 - The Origin of Delayed Polymorphism in Molecular Crystals Under Mechanochemical Conditions
N2 - We show that mechanochemically driven polymorphic transformations can require extremely long induction periods, which can be tuned from hours to days by changing ball milling energy. The robust design and interpretation of ball milling experiments must account for this unexpected kinetics that arises from energetic phenomena unique to the solid state. Detailed thermal analysis, combined with DFT simulations, indicates that these marked induction periods are associated with processes of mechanical activation. Correspondingly, we show that the pre‐activation of reagents can also lead to marked changes in the length of induction periods. Our findings demonstrate a new dimension for exerting control over polymorphic transformations in organic crystals. We expect mechanical activation to have a much broader implication across organic solid‐state mechanochemistry.
KW - General Chemistry
KW - Catalysis
KW - Organic Chemistry
PY - 2023
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-589219
SN - 0947-6539
SP - e202302150
PB - Wiley
AN - OPUS4-58921
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Feiler, Torvid
A1 - Yasuda, N.
A1 - Michalchuk, Adam
A1 - Emmerling, Franziska
A1 - Bhattacharya, Biswajit
T1 - Mechanistic Investigation of an Elastically Flexible Organic Crystal
N2 - Mechanical flexibility in molecular crystals is a fascinating behavior with potential for developing advanced technologies. However, the phenomenon of mechanical bending is poorly understood. We explore for the first time the atomistic origin of elastic bending in a single component organic crystal using a combination of μ-focus synchrotron X-ray diffraction and ab initio simulation.
KW - Flexible crystals
KW - DFT calculation
KW - Bending mechanism
PY - 2023
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-581949
SN - 1528-7483
VL - 23
IS - 9
SP - 6244
EP - 6249
PB - ACS Publications
AN - OPUS4-58194
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bornemann-Pfeiffer, Martin
A1 - Wolf, Jakob
A1 - Meyer, Klas
A1 - Kern, S.
A1 - Angelone, D.
A1 - Leonov, A.
A1 - Cronin, L.
A1 - Emmerling, Franziska
T1 - Standardization and control of Grignard reactions in a universal chemical synthesis machine using online NMR
T1 - Standardisierung und Kontrolle von Grignard-Reaktionen mittels Online-NMR in einer universellen chemischen Syntheseplattform
N2 - A big problem with the chemistry literature is that it is not standardized with respect to precise operational parameters, and real time corrections are hard to make without expert knowledge. This lack of context means difficult reproducibility because many steps are ambiguous, and hence depend on tacit knowledge. Here we present the integration of online NMR into an automated chemical synthesis machine (CSM aka. “Chemputer” which is capable of small-molecule synthesis using a universal programming language) to allow automated analysis and adjustment of reactions on the fly. The system was validated and benchmarked by using Grignard reactions which were chosen due to their importance in synthesis. The system was monitored in real time using online-NMR, and spectra were measured continuously during the reactions. This shows that the synthesis being done in the Chemputer can be dynamically controlled in response to feedback optimizing the reaction conditions according to the user requirements.
N2 - Ein Problem der chemischen Literatur ist die fehlende Standardisierung bezüglich genauer Bedingungen, auch Echtzeit-Korrekturen sind ohne Expertenwissen nur schwer möglich. Dieser Mangel an Details erschwert experimentelle Reproduzierbarkeit, da Schritte oft mehrdeutig sind und daher von implizitem Wissen abhängen. Hier präsentieren wir die Integration von Online-NMR Spektroskopie in eine automatisierte chemische Syntheseplattform (CSM aka. “Chemputer”, unter Verwendung einer universellen Programmiersprache zur Synthese kleiner Moleküle fähig), um eine automatisierte Analyse und Anpassung von Reaktionen im laufenden Betrieb zu ermöglichen. Das System wurde anhand von Grignard-Reaktionen, die aufgrund ihrer Bedeutung für die Synthese ausgewählt wurden, validiert und einem Härtetest unterzogen. Synthesen wurden in Echtzeit mit Online-NMR überwacht, und die Spektren wurden während der Reaktionen kontinuierlich aufgenommen und analysiert. Dies zeigt, dass der Chemputer dynamisch mittels einer Regelung kontrolliert werden kann, um die Reaktionsbedingungen entsprechend den Anforderungen des Benutzers zu optimieren.
KW - Grignard reaction
KW - NMR spectroscopy
KW - Process analytical technology
KW - Process control
KW - Grignard-Reaktion
KW - NMR-Spektroskopie
KW - Prozessanalytik
KW - Prozesskontrolle
PY - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-531260
SN - 1521-3773
SN - 1433-7851
N1 - Bibliografische Angaben für die deutsche Version: Angewandte Chemie 2021, Jg. 133, S. 1–7, ISSN 0044-8249, ISSN 1521-3757, https://doi.org/10.1002/ange.202106323 - Bibliographic information for the German version: Angewandte Chemie 2021, vol. 133, p. 1–7, ISSN 0044-8249, ISSN 1521-3757, https://doi.org/10.1002/ange.202106323
VL - 60
IS - 43
SP - 1
EP - 6
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-53126
LA - mul
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Gugin, Nikita
A1 - Villajos Collado, José Antonio
A1 - Dautain, O.
A1 - Maiwald, Michael
A1 - Emmerling, Franziska
T1 - Optimizing the Green Synthesis of ZIF-8 by Reactive Extrusion Using In Situ Raman Spectroscopy
N2 - We report the scale-up of a batch solid synthesis of zeolitic imidazolate framework-8 (ZIF-8) for reactive extrusion. The crystalline product forms in the extruder directly under the mixture of solid 2-methylimidazole and basic zinc carbonate in the presence of a catalytic amount of liquid. The process parameters such as temperature, liquid type, feeding rate, and linker excess were optimized using the setup specifically designed for in situ Raman spectroscopy. Highly crystalline ZIF-8 with a Brunauer–Emmett–Teller (BET) surface area of 1816 m2 g–1 was quantitatively prepared at mild temperature using a catalytic amount of ethanol and a small excess of the linker. Finally, we developed a simple and comprehensive approach to evaluating the environmental friendliness and scalability of metal–organic framework (MOF) syntheses in view of their large-scale production.
KW - Mechanochemistry
KW - In situ Raman
KW - Large-scale processing
KW - Metal−organic frameworks
KW - Twin-screw extrusion (TSE)
PY - 2023
U6 - https://doi.org/10.1021/acssuschemeng.2c07509
SN - 2168-0485
VL - 11
IS - 13
SP - 5175
EP - 5183
PB - ACS Publications
AN - OPUS4-57366
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Meurer, Maren
A1 - Arb, Hannes
A1 - Altmann, Korinna
T1 - Optimierung der Mikroplastik Analytik mittels TED-GC/MS sowie Reduktion von falsch positiven PE Werten durch beschleunigtes Lösemittelverfahren
N2 - Ein drastisch hoher Polyethylene Massenanteil wurde bei der Analytik der Umweltproben im Vergleich zu weiteren Polymeren festgestellt. Zu einem Überbefund des Polyethylene können strukturell verwandte Verbindungen wie z.B. Fette durch Signalüberlagerung führen. Mithilfe von beschleunigter Lösemittelextraktion soll die störende Komponente entfernt werden.
T2 - Die Wasser 2021
CY - Online meeting
DA - 10.05.2021
KW - Extraktion
KW - Mikroplastik
KW - ASE
KW - Polyethylene
PY - 2021
AN - OPUS4-53896
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Villajos Collado, José Antonio
A1 - Bienert, M.
A1 - Gugin, Nikita
A1 - Emmerling, Franziska
A1 - Maiwald, Michael
T1 - A database to select affordable MOFs for volumetric hydrogen cryoadsorption considering the cost of their linkers
N2 - Physical adsorption at cryogenic temperature (cryoadsorption) is a reversible mechanism that can reduce the pressure of conventional compressed gas storage systems. Metal–organic framework (MOF) materials are remarkable candidates due to the combination of high specific surface area and density which, in some cases, provide a high volumetric storage capacity. However, such extensive use of MOFs for this application requires the selection of affordable structures, easy to produce and made from feasible metallic and organic components. Herein, we introduce a MOF database detailing the crystallographic and porous properties of 3600 existing MOFs made from industrially relevant metals and their organic composition. The comparison of the available minimum costs of linkers allowed the creation of a database to select affordable structures with high potential for volumetric hydrogen storage by cryoadsorption, considering their composition based on individual or mixed building blocks. A user inter� face, available online, facilitates the selection of MOFs based on the properties or names of structures and linkers.
KW - MOF´s
PY - 2023
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-583619
VL - 4
IS - 18
SP - 4226
EP - 4237
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-58361
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -